All art is derivative. If I get inspired and copy an idea, the art is mine. If I take an artwork, modify it enough, fair use makes it mine. AI does the same, and it's not a difference in kind but volume. The anger from artists seems to come down to who gets the money. As usual, it's not artists. Authors, too, suffer from this system where the creatives who provide all the material are at the bottom and the distributors and owners get the bulk of the payout. Now, it's also tech. I'm thrilled my author friends can start creating images for their worlds and characters. I hate that non-artists get all the loot.