All arguments disputing a computable brain reduce to claiming that something exists beyond physics or claiming that physics is non-computable in some way. There is no evidence for either of these, Penrose's theory included.
Quantum physics is still physics. The fact that it's not computable (non-deterministic) is not even disputable at this point, it's the nature of reality.
The only questionable thing is whether quantum effects are essential in brain activity.
> The fact that it's not computable (non-deterministic) is not even disputable at this point, it's the nature of reality.
Of course it's disputable. There are at least two well known deterministic interpretations of quantum mechanics that are indistinguishable from orthodox QM, Many Worlds and Bohmian mechanics.
The only questionable thing is whether quantum effects are essential in brain activity.