> Nobody is going to stop buying Harry Potter books because they can get an LLM to spit out ~50 words from one of the books.

Not yet, but they'll stop buying books on niche technical subjects.

> Did Meta publish a book written by an LLM?

They don't need to publish a book to substitute original works. They substitute the original work every time they generate a response that is based on the book they substituted.

> I would consider training LLMs to be very much in line with those goals.

Because you're misunderstanding the premise. Original works are the ones that advance art and science. Those are the ones that are supposed to be protected by copyright.