I merely read the PDF articles you linked, then posted, verbatim, the primary relevant section I could find therein. Nowhere does it say that works involving humans in collaboration with AI can't be copyrighted. The conclusions linked merely state that copyright claims involving AI will be decided on a case by case basis. They MAY reject your claim, they may not. This is all new territory so it will get ironed out in time, however I don't think we've reached full legal consensus on the topic, even when limiting our scope to just US copyright law.
I'm interpreting your most recent reply to me as an implication that I'm taking the conclusions you yourself linked out of context. I'm trying to give the benefit of the doubt here, but the 3 linked PDF documents aren't "a mountain of evidence" supporting your argument. Maybe I missed something in one of those documents (very possible), but the conclusions are not how you imply.
Whether or not a specific git commit message correctly sites Claude usage or not may further muddy the waters more than IP lawyers are comfortable with at this time (and therefore add inherent risk to current and future copyright claims of said works), but those waters were far from crystal clear in the first place.
Again, IANAL, but from my limited layman perspective it does not appear the copyright office plans to, at this moment in time, concisely reject AI collaborated works from copyright.
Your most recent link (Finnegan) is from an IP lawyer consortium that says it's better to include attribution and disclosure of AI to avoid current and future claim rejections. Sounds like basic cover-your-ass lawyer speak, but I could be wrong.
Full disclosure: I primarily use AI (or rather agentic teams) as N sets of new eyeballs on the current problem at hand, to help debug or bounce ideas off of, so I don't really have much skin in this particular game involving direct code contributions spit out by LLMs. Those that have any risk aversion, should probably proceed with caution. I just find the upending of copyright (and many other) norms by GenAI morbidly fascinating.