Isn't that like asking whether YouTube videos or links to Twitter posts should be a violation of the terms of service?
AI is just a tool. It's what you use it for that is potentially irritating or detrimental to the community.
We already have ToS rules against spam, right wing talking points, kooky or extremist content, and graphic content, copyrighted material, etc.
What is the specific mischief posed by allowing people to use AI as part of their post that is not already covered by those rules? And, if so, wouldn't a more effective approach be adding that mischief to the list of no-no's than having endless debate over whether something was AI generated or not.
I mean I guess we could try to have a more explicit rule against posted misinformation that goes beyond "don't post right wing talking points" but I think that's going to be hard to enforce.
I don't personally have a horse in this race. I don't see the point of posting on a message board for fun if you are going to let AI write your posts for you. But I also don't see how a ban on AI would really work or what the justification for it would be. You'd waste a lot of time and resources trying to enforce it and you'd potentially make it harder for people to get the benefits (using it for research, quickly generated images for those of us who aren't remotely artistic, etc.)