Douthat cites data from the John Jay report (from where the above graph originates) to argue that "the moral/cultural/theological climate of the 1960s and 1970s encouraged a spike in sexual abuse." He continues:
This data informs the conservative Catholic argument that the post-Vatican II exodus of straight men from religious life and the spread of a sexually-active gay subculture within the priesthood is the abuse scandal’s “elephant in the sacristy.” Liberal Catholics might counter that the priesthood has always been disproportionately homosexual, and that the sexual revolution probably just encouraged psychologically healthy gay priests to give up on the church entirely, leaving behind a clerical population tilted toward repression, self-loathing and the dysfunctions of the closet. Whichever narrative you prefer, though, it’s hard to deny that something changed in the 1960s, and not for the better.
Ross responds to readers' criticisms here. His obvious fallacy is conflating reported cases of abuse with actual cases of abuse.
Reporting sexual abuse by a priest before the 1970s would have been extremely, extremely unlikely. Who would have believed you? How would you bring such a taboo subject up? Given the authoritative structure of the church, the reverence with which priests were treated, and the shame and stigma attached to all things sexual, the chances that a raped child would report a priest's abuse to the authorities or even his or her own family before the 1970s was minimal.