I disagree with your interpretation of how an AI works, but I think the way that AI works is pretty much irrelevant to the discussion in the first place. I think your argument stands completely the same regardless. Even if AI worked much like a human mind and was very intelligent and creative, I would still say that usage of an idea by AI without the consent of the original artist is fundamentally exploitative.

You can easily train an AI (with next to no human labor) to launder an artist's works, by using the artist's own works as reference. There's no human input or hard work involved, which is a factor in what dictates whether a work is transformative. I'd argue that if you can put a work into a machine, type in a prompt, and get a new work out, then you still haven't really transformed it. No matter how creative or novel the work is, the reality is that no human really put any effort into it, and it was built off the backs of unpaid and uncredited artists.

You could probably make an argument for being able to sell works made by an AI trained only on the public domain, but it still should not be copyrightable IMO, cause it's not a human creation.

TL;DR - No matter how creative an AI is, its works should not be considered transformative in a copyright sense, as no human did the transformation.