A well-regarded Hollywood insider recently suggested that sequels can represent “a sort of creative bankruptcy.” He was discussing Pixar, the legendary animation studio, and its avowed distaste for cheap spin-offs. More pointedly, he argued that if Pixar were only to make sequels, it would “wither and die.” Now, all kinds of industry experts say all kinds of things. But it is surely relevant that these observations were made by Ed Catmull, the president of Pixar, in his best-selling 2014 business-leadership book.

Yet here comes Cars 3, rolling into a theater near you this month. You may recall that the original Cars, released back in 2006, was widely judged to be the studio’s worst film to date. Cars 2, which followed five years later, was panned as even worse. And if Cars 3 isn’t disheartening enough, two of the three Pixar films in line after it are also sequels: The Incredibles 2 and (say it isn’t so!) Toy Story 4.

The painful verdict is all but indisputable: The golden era of Pixar is over. It was a 15-year run of unmatched commercial and creative excellence, beginning with Toy Story in 1995 and culminating with the extraordinary trifecta of wall-e in 2008, Up in 2009, and Toy Story 3 (yes, a sequel, but a great one) in 2010. Since then, other animation studios have made consistently better films. The stop-motion magicians at Laika have supplied such gems as Coraline and Kubo and the Two Strings. And, in a stunning reversal, Walt Disney Animation Studios—adrift at the time of its 2006 acquisition of the then-untouchable Pixar—has rebounded with such successes as Tangled, Wreck-It Ralph, Frozen, and Big Hero 6. One need only look at this year’s Oscars: Two Disney movies, Zootopia and Moana, were nominated for Best Animated Feature, and Zootopia won. Pixar’s Finding Dory was shut out altogether.

This thriving expansion of high-quality animated storytelling would not have been possible without Pixar. The studio literally reinvented the genre with Toy Story, the first computer-generated 3-D-animated feature film. Each subsequent Pixar release offered new feats of technical wizardry, from engineering the delicate trajectories of millions of individual strands of fur in 2001’s Monsters, Inc. to capturing the wondrous interplay between light and water in 2003’s Finding Nemo.

Even as others gradually caught up with Pixar’s visual artistry, the studio continued to tell stories of unparalleled depth and sophistication. Pixar’s signature achievement was to perfect a kind of crossover animated cinema that appealed equally to kids and adults. The key was managing to tell two stories at once, constructing a straightforward children’s story atop a more complex moral and narrative architecture. Up, for example, took a relatively conventional boy’s adventure tale and harnessed it to a moving, thoroughly grown-up story of loss, grief, and renewal.

The theme that the studio mined with greatest success during its first decade and a half was parenthood, whether real (Finding Nemo, The Incredibles) or implicit (Monsters, Inc., Up). Pixar’s distinctive insight into parent–child relations stood out from the start, in Toy Story, and lost none of its power in two innovative and unified sequels. “Who would want to see a movie about a little boy who plays with dolls?,” Michael Eisner, then the CEO of Disney, obtusely asked when told of plans for the Pixar debut. (Disney was to co-finance it.) But the film’s creative premise is precisely—and crucially—the reverse: Toy Story is a movie about dolls who want to be played with by a little boy.

That inversion complicates and intensifies the film’s emotional power. In their desire for the attention of 6-year-old Andy, the toys—particularly Woody the cowboy and Buzz Lightyear the spaceman—mirror children’s eagerness to capture their parents’ attention. Yet of course Andy is not a parent. He’s a child, and it’s the toys that are mostly accorded the role of grown-ups. (An astute bit of psychological realism: Andy, like most kids, uses them to pantomime adulthood.) So even as, on one level, Woody and Buzz act as children to Andy’s parent, on another they act as parents to Andy’s child: His happiness is their responsibility, and they will resort to the most-extreme measures imaginable to ensure it.

Toy Story thrilled adults and kids alike with this canny and moving portrayal of the parent–child bond. And its creators seemed to appreciate what a rich emotional and dramatic vein they had tapped into. Following the movie’s success, Disney, then the distributor for Pixar, pushed for the production of a quickly made, direct-to-video sequel. Such second-tier fare has long been a lucrative Disney sideline, generally produced by the in-house subsidiary Disneytoon Studios. (Examples of its output include such classics as The Lion King 1 ½ and The Little Mermaid: Ariel’s Beginning.) But Pixar rebelled, on the grounds that the studio aspired only to excellence. Instead it produced, at breakneck pace, a theatrical-release sequel that met the high bar set by the original.

In his 2014 book, Creativity, Inc., Catmull describes the episode as “the crucible in which Pixar’s true identity was forged.” Toy Story 2 (1999) didn’t merely equal the original. The sequel enriched it, presenting Woody with a new but related quasi-parental dilemma: Should he spend the rest of his life untouched and pristine on the shelf of a vintage-toy collector? Or should he return to enjoy loving play with a rowdy boy (as the movie opens, Andy has inadvertently torn Woody’s arm half off) who will ultimately outgrow and discard him? In the end, Woody opts for the messy combination of joy and sacrifice with Andy, as apt a metaphor for parenthood as you’re likely to find. And with its foreshadowing of eventual abandonment, Toy Story 2 laid the groundwork for still further thematic development. That promise was fulfilled almost a decade later, in Toy Story 3, a concluding chapter in which Andy finally heads off to college and a new life, leaving behind toys and parents alike.

Almost as renowned as Pixar’s onscreen magic throughout this period was its collaborative culture. Under the leadership of the studio’s founder and creative guru, John Lasseter, it relied heavily on a small, mutually reinforcing group of gifted animators and editors: Pete Docter, Andrew Stanton, Joe Ranft, Lee Unkrich, and Brad Bird (who joined Pixar in 2000). Known informally as the “Braintrust,” the group grew over time, but these five men and Lasseter stood out for their collegial self-criticism and ethos of constant refinement in the pursuit of perfection. So strong was their synergy that every time outside directors were brought in to handle a film (as they were for Toy Story 2 and Ratatouille), they were ultimately replaced by one of the early members of the Braintrust. In 2004, a Disney subsidiary, Circle 7 Animation, was created to produce sequels to Pixar films. Dubbed “Pixaren’t,” its doors were soon closed and all its scripts scrapped.

And then, after Toy Story 3, the Pixar magic began to fade. The last film of the golden era, it was also the first film begun after Disney acquired Pixar for $7.4 billion in 2006, when Lasseter and Catmull were made, respectively, the chief creative officer and the president of both studios. The sequels that followed—Cars 2 (a spy spoof) in 2011 and Monsters University (a college farce) in 2013—lacked any thematic or emotional connection to the movies that spawned them. Though better than either of those two, Brave, Pixar’s 2012 foray into princessdom, was a disappointment as well. The studio rallied with Inside Out in 2015. But the inferior The Good Dinosaur (also in 2015) and last year’s mediocre Finding Dory only confirmed the overall decline, which was particularly noticeable in comparison with the revival under way over at Disney Animation.

Catmull once said that Pixar’s intent was to make one sequel for every two original features. The ratio since 2010 has been closer to the inverse. Especially lamentable was the announcement, in 2014, of plans for Toy Story 4. The narrative and emotional arc of the trilogy had clearly been completed with Andy’s departure for college. The third installment had even closed, lovingly, with a shot that neatly mirrored the opening shot of the first film: the fluffy-white-clouds-on-blue-sky wallpaper of young Andy’s bedroom in Toy Story giving way to real white clouds in the real blue sky. Yet instead of concluding on that touching note, Pixar has opted for what has been described as a “franchise reboot”—surely the most dispiriting phrase in contemporary cinema.

The differing trajectories of Pixar and Disney Animation have hardly gone unremarked. At the time of the merger, Disney was “demoralized” and “failing as a company,” Catmull observed a couple of years ago, before adding, “Disney is now successful.” About Pixar, he was less sanguine: “There are major issues we’re addressing at Pixar now.”

Lasseter and Catmull do, after all, have only so many hours in their days to devote to their competing obligations at Pixar and Disney, as Catmull made clear in his book. If the studio with the corporate parent’s name on it took precedence, that would hardly be a surprise. Nor would it be surprising if the dilution of focus took a toll, given how dependent Pixar’s culture was on an intimate circle of innovative minds. (Other Braintrust members have been pursuing interests beyond Pixar too: Stanton explored live-action filmmaking with John Carter, and Bird did the same with Mission: Impossible—Ghost Protocol and Tomorrowland.)

Still, the erosion of Pixar’s uncompromising creative independence can’t be reduced to a case of inadequate oversight. The Disney merger seems to have brought with it new imperatives. Pixar has always been very good at making money, but historically it did so largely on its own terms. The studio, remember, rejected a low-quality direct-to-video Toy Story 2, and instead worked round the clock to come up with another tour de force. But Lasseter, among his other obligations, now oversees Disneytoon Studios as well. In that capacity he served as the executive producer of 2013’s Planes and its 2014 sequel, Planes: Fire & Rescue. The two movies are—like virtually all Disneytoon films—shameless, derivative cash grabs. What makes them unique is that they are also explicit spin-offs of Pixar’s Cars franchise, a development that would have been almost unimaginable before the merger. As Lasseter himself explained, “By expanding the Cars world, Planes gave us a whole new set of fun-filled situations.”

Not to mention a whole new set of toys. Merchandising has, naturally, always been a temptation for Pixar (as for any purveyor of kids’ movies). And Disney has played a central role in the marketing and merchandising of Pixar films since 1991. But when you become a division of the largest entertainment conglomerate in the history of the world, commercial opportunities multiply exponentially. There are a dozen Disney theme parks scattered across the globe in need of, well, themes for their rides. So the year after its acquisition of Pixar, Disney announced that it would open Toy Story Midway Mania the following year at both Disney World and Disney California Adventure. Later in 2007, Disney announced a $1.1 billion redesign of its failing California Adventure park, featuring a new, 12-acre Cars Land. Additional Toy Story– and Finding Nemo–themed rides are in the works in Shanghai and Tokyo.

Indeed, the overlap between the Pixar movies that beget sequels and the movies that inspire rides at Disney amusement parks is all but total. Theme-park rides are premised on an awareness of the theme in question, and young parkgoers are less likely to be familiar with movies that are more than a decade old. If you want them clamoring to experience Toy Story Midway Mania, they’ll need a Toy Story 4. Cars Land could use a Cars 3, and Finding Nemo–associated rides were due a Finding Dory. Who better to preside over all this corporate synergy than Lasseter—who, to note yet one more of his many titles, is also the “principal creative adviser” for Walt Disney Imagineering, the subsidiary responsible for designing the rides?

Pixar has promised that after the upcoming glut of sequels, the studio will focus on original features. But we’re grown-ups, and though the once inimitable studio has taught us to believe in renewal, it has also trained us in grief and loss. I’m not sure I dare to expect much more of what used to make Pixar Pixar: the idiosyncratic stories, the deep emotional resonance, the subtle themes that don’t easily translate into amusement-park rides. I’m thinking of the heartbreaking, waltz-set “Married Life” segment of Up, which packs more emotion into four minutes than most Oscar-nominated dramas manage in their entire running time. Or the wistful solitude of wall-e’s robotic protagonist, left behind on Earth to clean up his creators’ mess. Or Anton Ego’s artful critique of criticism at the end of Ratatouille, arguably the slyest words on the subject since Addison DeWitt’s in All About Eve.

None of these films is scheduled to have a sequel. And none is particularly suited to becoming a theme-park ride (though Disney unveiled Ratatouille: The Adventure at, of course, Disneyland Paris). Which can’t help but raise the question: Would Pixar even bother making those pictures anymore?