I’m not a lawyer, but here is why I believe a class action lawsuit is correct;
“AI” is just fancy speak for “complex math program”. If I make a program that’s simply given an arbitrary input then, thought math operations, outputs Microsoft copyright code, am I in the clear just because it’s “AI”? I think they would sue the heck out of me if I did that, and I believe the opposite should be true as well.
I’m sure my own open source code is in that thing. I did not see any attributions, thus they break the fundamentals of open source.
In the spirit of Rick Sanchez; It’s just compression with extra steps.
Your code is not in that thing. That thing has merely read your code and adjusted its own generative code.
It is not directly using your code any more than programmers are using print statements. A book can be copyrighted, the vocabulary of language cannot. A particular program can be copyrighted, but snippets of it cannot, especially when they are used in a different context.
And that is why this lawsuit is dead on arrival.
Am I violating your copyright? Are you entitled to do that?
To make it funnier: Say instead of the .xz, I "compress" it via π compression [1]. So what I share with you is a pair of π indices and data lengths for each of them, from which you can "reconstruct" the audio. Am I illegally violating your copyrights by sharing that?