Everything is open-source if you know assembler
Weights are basically algorithm. It is not even obfuscated. Companies successfully produce derivative works from them, what is the problem?
One does not require git history for any Foss project, the exact way the code was produced IA not the requirement, it is the reproducibility that matters.
Even AI developers themselves cannot train AI in the same way as one compiles a program. Storing all the necessary data is just not feasible. To achieve results comparable to modern flagship models, one needs to obtain data in real time, use large amounts of generated data that is deleted after single use. And the training algorithm itself is not deterministic.
And I still fail to see how this is any different from requiring a git commit history. There is an algorithm present - that's it. It has no other forms in which it can be presented.