No. I looked into this a lot for a dating app I ran and no algorithms came close to human moderation, even for images you'd consider are obviously pornographic,

No. I looked into this a lot for a dating app I ran and no algorithms came close to human moderation, even for images you'd consider are obviously pornographic, which can get expensive. A funny idea I had was to reverse the whole system - feed UGC content of a site that's supposed to be SFW into a porn site which is definitely NSFW, one that has lots of thumbnails. The ones that don't get any clicks to enlarge probably aren't porn and can pass the test :)