I don’t recall exactly but this is the gist that I remember from a /r/subredditdrama post I read over a year ago

“Real news” sub reddits let porn, nsfw content, onlyfans and whatnot on them because they were not actively or thoroughly moderated. Some users were upset,To emphasize their point started posting nsfw anime pictures.

Someone decided they had enough and broke off into their own sub reddit that has actual news and it was called /r/animetitties or something.