You act as if the internet was like a high society book club - all the previous articles were written by ivy league grads.
I recall geocities, angelfire, all the chans.
The internet has always been a cesspool with little islands of quality floating in a proverbial sewage of human output. In theory AI slop will improve.
A racist, sexist, ignorant online community of humans 20 years ago, if it is still active, is almost certainly still a racist, sexist, and ignorant community today.
So your straw man is that the internet already had bad stuff on it? Cmon, you can do better. Adding more bad to bad is still bad.
Being able to name especially egregious forums is the point. AI slop isn't worse than preceding slop, but it is more widespread, partly because it's more socially acceptable than racism, sexism, and ignorance, and partly because it's harder to identify.
Similarly, email spam that is easy to automatically categorize is not a problem.
Making slop less sloppy makes the problem worse, not better. You could claim that that's only up to a threshold, but there's a pretty strong information theoretic argument against that.