There's a lot of strange pornography on the web, even if you exclude the numerous Tor onion services. Here is a site that tries to randomly sample and display (like a proxy, never linking to the source) recently-circulating pornography: https://rnsaffn.com/zg3/
Observing the stream of images, it's clear that niche human sexual interests are both unpredictable and sometimes shocking. It's also clear that AI-generated pornography is not as popular as you might imagine. Many people don't like it.
I imagine most of us prefer to know that a real person is on the other side of an image, but I'm sure there are plenty of us who don't care. In any case, AI porn still has a certain vibe that is detectable.
I let this run for 50 or so images and more than half were definitely AI generated. Other than one (real-looking) shot of clothed BDSM everything was completely vanilla. Maybe I tried the wrong moment.
So you hit a run of maybe 25 (related) AI-generated images that were grouped together. Images are bundled together and the bundles are randomly selected. You "tuned in" to maybe 3 or 4 bundles and should try again, as that's definitely not a representative sample. The stream is effectively infinite and continuously updating.
For example, you'll find that elder porn is more common than AI-generated porn, perhaps because some older men like looking at older women. You'll even find that rope binding and humiliation and grotesque obesity are more common than AI-generated porn.
But of course, what you call "completely vanilla" is the most common variety of pornography, as you would expect. Obviously that's what most people are looking for.
Maybe they look better in motion since they're stills from videos, but those AI faces the article shows look terrible. They look rubbery and give me an uncanny valley feeling.
I highly recommend the Charles Strauss novel "Rule 34" for a vision of where this will shortly be and the impact on the legal system and law enforcement.
Observing the stream of images, it's clear that niche human sexual interests are both unpredictable and sometimes shocking. It's also clear that AI-generated pornography is not as popular as you might imagine. Many people don't like it.