They almost always get removed or deleted eventually, but sometimes they'll get upvoted for a few hours until an eagle eyed user spots evidence and calls it out.

It's also not OPs fault most of the time. It's hard to spot them

I see no GenAI content here whatsoever except for what's posted on communities specifically meant for it.

In a general sense, absolutely, but there are still a good number of pro-AI communities around here that typically keep to their own bubbles. Anyone browsing by All will inevitably see them come up here and there.

I also see AI-gen content make it to the top of larger, more general communities like Lemmy Shitpost every now and then. Usually when it's harder to tell that it was generated by AI. When it gets called out, you'll typically see more upvotes than downvotes, but there will inevitably be some AI sympathist or two in the replies who won't hesitate to go off about how it's not a big deal/it's just a meme/there's nothing inherently wrong with AI/etc.