There are two types of people who are happy that Piers Morgan Tonight is over: gun rights activists who didn't like the way he talked about guns, and transgender rights activists who didn't like the way he talked about transgender women. Both groups think they're part of the reason — if not the major reason — his show was cancelled. Either way, both groups are glad to see him go.
Gun Rights Activists
David Carr, who broke the story for The New York Times, made the argument that low ratings contributed to both CNN and Morgan deciding to end the show. Carr suggests those ratings were the result of Morgan being a jerk ("There have been times when the CNN host Piers Morgan didn’t seem to like America very much — and American audiences have been more than willing to return the favor," he writes), Morgan being too exotically British for his "intrinsically provincial" audience and, in the second half of the piece, guns:
Mr. Morgan’s approach to gun regulation was more akin to King George III, peering down his nose at the unruly colonies and wondering how to bring the savages to heel ... He regrets none of it, but clearly understands his scolding of “stupid” opponents of gun laws was not everyone’s cup of tea.
Carr's story was a "cheery start" to National Review's "Daily Jolt" news roundup. In "Pier-ing Into the Abyss of Cancellation," Jim Geraghty outlined exactly why there's no love lost between Morgan and conservatives. The issue wasn't that he was too British, or only talked about British issues, but that "he kept communicating to an American audience why he thought their country was so bad." Morgan was called out on his views many times with no change, which is why Geraghty closes with this dig: "And he never changed. Instead, viewers changed the channel."