I think the main thing is citation. If AI is used, the poster should include a statement such as, "This content (or section) was AI generated." Or, perhaps, "This post was written with assistance of AI." It then goes from trying to pull one over on people to being honest.

This is assuming the "poster" is a human, not a bot. In this case, the human poster is doing this: telling AI to generate content, then posting that content as him or herself, and effectively trying to pass it off as him or herself. I'd say there are shades of gray, but it's not entirely honest.

I once had a professor talking about plagiarism. He said something like: Why would you even plagiarize and try to use someone else's work? You can still use others' work, but just cite it! Suddenly, it goes from "stealing" and you're the bad guy to become "academic research" and you get praised for it.