It is not about tarballs, but about derived work.
It is not about tarballs, but about derived work. And if a distribution is a derived work, that is what the dispute is about.
The GPL is about freedom, but NOT freedom of the developer. The developer doesn't matter in the view of the GPL. It is all about the freedom of the user. It tries to protect the user from proprietary software; if you release a software under a permissive license one could use it to write proprietary software.
Most people I know think that the GPL is about the freedom of use for your own program. That is a wrong conclusion.