https://www.psychologytoday.com/us/blog/all-about-sex/201601/evidence-mounts-more-porn-less-sexual-assault
As far as porn is concerned, some studies even indicate lower crime rates and abusers having consumed *less* porn than other groups.
I'm less concerned about that though, and more whether anyone's been harmed by it. If it involves consenting adults / non-existent people, I think that's fine.
I don't really care about particular kinks, even if they're real weird to me, hey, whatever makes someone happy.