One might ask: Under what circumstances would AI art be acceptable then?
For example, does it really matter if these models are created by large corporations? I don't see what the legal or ethical difference would be if it was an individual who created such a model.
Is it relevant whether their artworks were used in the training data? Well, what if a new model that is trained only on public domain photos, videos and artworks turns out to be just as capable? What if a future model is able to imitate an art style after seeing merely one or two examples of it?
It might just be a matter of time until such a model is developed. Would it be alright then? If not, why?
(Personally, I think it's the responsibility of the AI model user to use the AI art legally and ethically, as if the user made the image themselves.)