Care to point to those Ls in court? Because as far as I'm aware they are mostly still ongoing and no legal consensus has been established.

It's also a bit disingenuous to boil his argument down to what you did, as that's obviously not what he said. You would most likely agree that a human would produce transformative works even when basing most of their knowledge on that of another (such as tracing).

Ideas are not copyrightable, and neither are styles. You could use that understanding of another's work to create forgeries of their work, but hence why there exist protections against forgeries. But just making something in the style of another does not constitute infringement.

EDIT:

This was pretty much the only update on a currently running lawsuit I could find: https://www.reuters.com/legal/litigation/us-judge-finds-flaws-artists-lawsuit-against-ai-companies-2023-07-19/

"U.S. District Judge William Orrick said during a hearing in San Francisco on Wednesday that he was inclined to dismiss most of a lawsuit brought by a group of artists against generative artificial intelligence companies, though he would allow them to file a new complaint."

"The judge also said the artists were unlikely to succeed on their claim that images generated by the systems based on text prompts using their names violated their copyrights.

"I don't think the claim regarding output images is plausible at the moment, because there's no substantial similarity" between images created by the artists and the AI systems, Orrick said."

Hard to call that an L, so I'm eagerly awaiting them.