The problem with AI is not even their developers fully understand how they work, and they’re not standardized, so there isn’t a one size fits all solution for dealing with them. The amount of different ways a model may or may not fail in is so large, that any particular fail mode might as well be random.

Even if you do manage to find something like a captcha that can filter out most AI models, it’s as much a matter of time, as it is a matter of randomness for some developer to find a way to bypass it, even if accidentally. Case and point: m.youtube.com/watch?v=iuR9EJbXHKg