Only a very small fraction of Apple's employees will ever attempt to be entrepreneurs. It's no threat to the extreme majority of all employees in Silicon Valley. Outsized total compensation and great benefits is all most tech workers in SV are after, entirely reasonably so.
I agree that it will scare off many employees that are heavily inclined toward starting their own thing. It's an interesting question as to whether companies like Apple are better off or worse off in that scenario. People that are particularly entrepreneur-minded often don't make for great employees (I'm in that group).