Unsurprising, but as with twitter, the idea of a corporation running these kinds of sites always eventually fails.
People "don't want to deal with" the messy world of open standards, of different web forums for different things, federation... I mean, I get it, but that just ends up meaning they fall for the same twitter/myspace/facebook/walmart.com trick again, over and over and over.
Somebody else posted the enshittification link — that's what is happening here. Like it always does.
The AI thing is an obvious red herring anyway. Plenty of ways they could address that without harming third party clients for human readers, but they want to strangle those clients. As twitter did before them, as they all do eventually.
They tend to do it as soon as they feel they've tricked enough people to investing enough of their attention in them that the users won't just leave. Which in reddit's case they probably have, considering how often search engines propose adding "reddit" to whatever my search string is.