The complexity described seems to be resting on the unestablished idea that weights are copyrightable in the first place. If they're not, then presumably "available weights", "ethical weights", and "open weights" are all the same: open weights. Either your weights are under NDA and presumably considered to be a trade secret, or they are public, and the words in your "license" mean absolutely nothing? That seems like…
Furthermore, if weights are copyrightable, wouldn't this make the issue of training data licenses even more urgent? IANAL, but if weights are IP, wouldn't they constitute a "derived work" of the training data?
On the other end of the spectrum, AI generated content couldn't be copyrighted if there is no human involvement. If someone asks GPT to write 1000 poems, it couldn't be copyrighted.