I see. The question here is not if there will be proprietary software: there will be. The question is which of that proprietary software runs on the CPU.

I'm pretty sure no closed source software runs on the CPU. As for the hardware that depends on your definition. Hardware often has firmware in ROM. That you now feed that firmware on bootup instead of it being in ROM just allows you to update the firmware from the manufacturer. If that's running proprietary software depends on your definition.