All law is arbitrary. Intellectual property law perhaps most of all.
Famously, the output from monkey "artists" was found to be non-copyrightable even though a monkey's brain is much more similar to ours than an LLM.
[1] https://en.wikipedia.org/wiki/Monkey_selfie_copyright_disput...
If IP law is arbitrary, we get to choose between IP law that makes LLMs propagate the GPL and law that doesn't. It's a policy switch we can toggle whenever want. Why would anyone want the propagates-GPL option when this setting would make LLMs much less useful for basically zero economic benefit? That's the legal "policy setting" you choose when you basically want to stall AI progress, and it's not going to stall China's progress.