Obviously, it is, since the only mechanism copyleft licenses have to claim/poison things the licensed material “touches” is the copyright doctrine of derivative works, and the licensable exclusive rights the original work’s copyright owner has to create derivative works.
This is why one company I worked for refused to let us use Webpack 1.x- a dependency of a dependency was an ancient npm module from the time that adding licenses to modules wasn't very common. It wasnt until the 2.x line came out that they finally updated to a version that updated to a version that didn't have that problem.
Yet my comparison of the human brain still stands, I believe.
Just because you learned about something in art class from looking at a copyrighted work doesn’t make everything you produce after that a derivative work.
This seems reasonable at first, but not the more I think about it. Copyright is not like an AGPL software license that claims/poisons everything it touches.
The NN is not an artistic work and probably should not be considered a derivative work any more than your brain or memory of a copyrighted work should be considered a derivative work. Likewise, the outputted work of a NN is not automatically a derivative work any more than the work of an artist that has been inspired by other artists' copyrighted content is. That's just not how copyright works.