I am still torn on this issue. On the one hand, it feels like a copyright violation when other people's works are used to train an ML model. On the other hand, it is not a copyright infringement if I paint a picture in the Studio Ghibli style myself. The question is whether removing a ‘skill requirement’ for replication is sufficient grounds to determine a violation.
None of the training data was originally drawn by OpenAI. OpenAI also actively monetizes that work.