I think you're missing the deeper point. Whether or not the Copyright Office intends to assert authorial essentialism, it's doing so in effect. And when metaphysical language about "creative essence" becomes encoded in policy and enforced by courts, it's not just metaphor. It's law.

Calling it "spirit of the law" doesn't let them off the hook. If you enshrine a metaphysics that treats human-authored works as ontologically distinct kinds of data, imbued with some persistent essence that radiates rights regardless of use, you're not interpreting the law, you're institutionalizing a theology of authorship.

And yes, I care less about their intentions than about the system they're building. That system is now enforcing metaphysical categories with legal teeth. That's the problem.