If an AI is able to consistently create content that doesn't break any of the forum's rules (good quality, on-topic, not just a padded word salad, no plagiarism, etc, etc),
I, for one, welcome our new machine overlords. Otherwise, content that violates the rules, AI or human produced, can already be dealt with with our current rules and policies in mind.
So, in theory if someone somehow managed to farm, let's say 5 accounts up to Full member and Senior member and somehow implemented an AI for those accounts to interact around here while joined a signature campaign or a bounty, so the single person behind those accounts can get all the economical benefits, that would be acceptable as long as the quality of those posts are good enough and on-topic? Right?
All that matters is that those users don't break the rules. If they don't, then yes, there's nothing against them operating several AI powered accounts though at that point, I'd be more worried about that AI doing things outside Bitcointalk as opposed to farming signature campaigns.
Just posting something on-topic , semi-correct and coherent doesn't necessarily mean the post isn't low value. That quality is what I feel a lot of AI generated content is gonna lack (and yes I'm aware of the recemt developments in that area).