So outputs are definitely not derivative work of training data, only weights? For this exact code that github is using, anything called "AI", or any computer code at all which produces work based in whole or in part on input data?

And for which jurisdictions has this been established? What is the legal argument that "weights" are derivative but output is not?

I'm surprised it's so clear cut as you say, but I haven't really been following the whole kerfuffle.