That would assume that randomness is the only quantum property that the brain would use. The possiblity of quantum computation demonstrates that there is more that could he possible.
Your earlier comment certainly appeared to be suggesting the brain uses quantum phenomena as an RNG. Are you instead suggesting the brain is a quantum computer?
The purpose of the example in my first comment was to show that quantum phenomena can influence macroscopic phenomena, not as an example of an RNG. It was probably a bad choice as everyone took it to mean an RNG. Quantum phenomena are not needed for this.
