If it were a derivative work[1] (and sufficiently transformational) then it's allowed under current copyright law and might not be the slam dunk ruling you were hoping for.
"sufficiently transformational" is carrying a lot of water here. At minimum it would cloud the issue and might expose anyone using AI to lawsuits where they'd potentially have to defend each generated image.
Oh, interesting, I didn't realize that's how it worked. Thanks for the additional context around this. Guess it's not as upending as I thought it could be.