I don't think that's true. I don't recall ever enabling porn titles but it recommends them to me even though I have never purchased or played one. If I ever had intentionally enabled that would have to have been more than a decade ago because I have no memory of it whatsoever.
Yeah I'm pretty certain it is not true. I think it turned itself on after a buddy bought me that Catherine game. Which was funny AF and a good play. I'm sure I could disable it but I always enjoy the wtf when it pops in my que. Plus it prompted flip witch which looks pretty good on my backlog.
It's amazing that people still downvote you, even though you have evidence and all they have is "I don't remember toggling this specific option in my multi-year account".
I also have a multi-year account (10+ years I believe). The only reason I see nsfw games on my store is because I went to the settings and toggled on that option, before that there were no porn games.
That option is toggled off by default, if you see porn games you toggled it on at some time, you might just not remember.