alt Hacker NewsEverywhere (reddit, YouTube, Spotify) need to have a button to flag and then flag as ai. Reddit really has it buried in multiple levels of menus.
People are pretty darn good now at spotting ai.
An alternative is just use ai to look at the comments. Almost anything with AI has comments complaining about it.
All of these sites need to deal with it because it does drive away users.
And, as always, flagging will be abused to downrank content that people/bots/spammers/scummy-businesses/etc. would prefer you not to see.