Something big is happening, as Reddit seems to have purged literally every NSFW sub they know. Reason is always "unmoderated" despite some of the banned subreddits being fully moderated.
Edit: seems to have been a bug in automation (thanks @lefty7283@lemmy.world):
https://old.reddit.com/r/ModSupport/comments/1ii67mt/_/mb3fewv
It's still a good reminder on how quickly a community (or communities) thousands of people enjoy and in some cases rely upon can disappear.
My experience is that modern NSFW on tumblr is just porn bots. You used to get really nice, high quality slutty art for whatever TV show or movie character tripped your trigger. Now they have an Ai bot that's trained itself to flag black and white sfw sketches but not straight up literal tiddy drop videos with spam links below them.