I see it on forums now too. On Reddit, midsized subs that get a mild amount of traffic get these brand new accounts that post what reads like an amalgam of past posts. Often in help forums where people ask questions.

They have that uncanny thing where yes it's on topic, but also not how a human would likely ask exactly AND they always let slip in just a hint of human drama that really draws in other users...

They almost never respond to comments, when they do it's pretty clear they're AI (much like the response in this story).

I've unsubscribed from a good half dozen subs in the past few months because of it.