How is it against freedom 4? You can distribute modified versions to the end of the world. You just don't get access to future modifications made by Red Hat. You are not entitled, neither legally nor morally, to Red Hat's future modifications.
> Sure, not legally. Just de-facto. Or to use some reductio ad absurdum, you can exercise all your freedoms, but you will be killed for it, is not very free, is it?