@Astrid
I don't know of a good argument against AI art tools in general; I don't think that gatekeeping around what "really counts as art", is a particularly good use of anyone's time.
There is an argument that at the moment the major AI art tools were created by making unauthorized use of a whole bunch of works by living artists, and those artists ought to be made whole, so to speak, either by the legal system, or by some sort of out of court settlement.
I don't know exactly where I stand on that, and obviously it doesn't worry me so much that I've avoided using Midjourney (25,000 Club any day now!).
But I would like to see that argument at least have its day in court.
I wrote a little bit about it over on writefreely: https://paper.wf/ceoln/ai-art-tools-the-way-s-forward