Fair enough, if that's is so, there's even less of a case to be made. The person inputting variables (i.e a prompt) into the model that prints out non-fair use outputs would be at fault. The end work would be the actual object subject to litigation. It's just a tool then. The current system still stands then.
Arguing a trained model is infringing would then be like arguing the manufacturers of my monitor were infringing as it contained the very same RGB.as the artist.