This is a fast path to open source irrelevancy, since the US copyright office has deemed LLM outputs to be uncopyrightable.
Open source != copyrighted. Public domain source code is also open source.
I hate this trend I see of the FOSS movement retreating from the foundational principle that it started on: Free Sharing of Software.
Not shareware, not 'libre but not gratis', not 'buy me a coffee to get access to the code on my patreon', not 'free to look at but not to use as source code': free period. Libre and gratis.
These non-lawyers traipsing in to make claims about the effect of AI on open source licensing are giving me big "I release my code but only if I can 1) get paid for it and 2) control who and how it's used" vibes. That's what's 'hollowing-out' open source.
value leaks out of the project
What value? Value to whom? The value of source code is what it does, i.e. the program it compiles or is interpreted into. That doesn't change by someone else using it differently than you. Google taking Linux and spinning off Android doesn't "hurt" Linux. It doesn't decrease the 'value'. There's no universal counter out there that says, "this GPLv2 attribution appears more than someone else's, so therefore this project is more valuable", that is being eroded if a company goes and uses it without reprinting the license notice as well. OSS licenses have never prevented that.
I said it before the last time FOSS came up, and I'll say it again:
FOSS is about propagating software to as many people as possible, to help as many people as possible. It's not about creating legal barriers to diminish the power of corporations; making tools available to people that are better and cheaper will do that naturally (and you were never going to beat the corpo lawyers anyways trying to enforce licenses).
If your zeal to prevent corporations from ever misusing FOSS leads you to remove some aspect of it (free, open, or source), then you've cut off your nose to spite your face.