> but we all have training by looking at copywrited[sic] source code at some time.
The single word "training" is here being used to describe two very different processes; what an LLM does with text during training is at basically every step fundamentally distinct from what a human does with text.
Word embedding and gradient descent just aren't anything at all like reading text!
Indeed, but that's just a misdirection. We don't actually know how a human brain learns, so it is hard to base any kind of legal definition on that difference. Obviously there are massive differences but what those differences are is something you can debate just about forever.
I have a lot of music in my head that I've listened to for decades. I could probably replicate it note-for-note given the right gear and enough time. But that would not make any of my output copyrightable works. But if I doodle for three minutes on the piano, even if it is going to be terrible that is an original work.