This has little to do with GPL,
I agree. It was just a joke.
and everything to do with RHL developers
being unable to view/modify if necessary the nvidia driver source. Once it's "included" in the distro, then steps have to be made to make sure that it'll work with all other newer software as it comes out, such as new kernels, new XFree86, all that fun stuff.
Absolutely. I've heard Alan Cox speak on this matter much more eloquently than I can put it.