Yeah, I don't get that argument. "Apple is funding LLVM, therefore it is getting better than GCC!". They are only funding it because it advances their goals. The moment they get what they want they will drop it or look for ways to keep the advantage all to themselves.
Everyone only does anything if it advances their goals. Luckily Apple's goals w.r.t. LLVM are the same as everyone else's: have a high-quality compiler backend.
The same could be said about non-corporate contributions. "People only contribute as long as they have a personal itch to scratch. The moment they get what they want, you're on your own again".
That's always been the deal. Open source is not a guarantee of free support forever! It's a guarantee that you can always fork and keep using the project (or even developing it further)