This is not the final word on the subject. This is just a court's ruling. Somebody will appeal it.
And it ruled it's okay to train your AI with books under two circumstances. You paid for the book and the so-called AI doesn't imitate the authors' voices. They didn't initially pay for the books so they have another trial to figure out a penalty for that.
And I personally don't buy the no imitation thing. You can make a model that does nothing else but create sloshfic. I think that's what the plaintiffs' lawyers will appeal the decision about.