I think that unless you can clearly show that an "AI" is not a form of compression, the question of copyright is orthogonal. The copyrights that apply to a zip file may be ill-defined concepts to you, but it's not really important to the core question which is: how are model weights different from a zip file? If you put unambiguously copyrighted content into a zip file, most people would agree that the copyright applies to the zip file. So by analogy if you put copyrighted content into model weights, the copyright applies to the model weights. Issues such as what constitutes fair use comes up, but fair use is permissible copyright infringement, not absence of copyright. And that's where the question of how lossy a compression algorithm has to be to be considered "fair use". In all likelihood it's the specifics of the use itself (rather than technology or method details used) that matters.