Similarly, there may be a layer below neurons -- microtubules. Something that many neuroscientists and AI researchers don't want to consider seriously, primarily because we're very limited in our ability to examine, interact, and model that layer.
It also throws off by orders of magnitude the effort which would be required to fully model an organism neural behavior.
There may be that layer, but is there evidence for that layer, and I'm not talking about that certain physicists hypothesis about microtubules and free will.
Sir Roger Penrose was investigating non-computability versus computability in brain behavior. I am not sure he even mentions free will.
This highlights some of the unfortunate tensions in this debate, where people may feel obliged to hold to a literal materialism along with a computational theory of mind, and vigorously shoot down anything that threatens to unsettle that somewhat dogmatic position, for fear of strengthening the position of fundamentalist religious believers. In short, it is primarily a political sentiment, not a scientific one.
We should be able to follow where evidence and rational argument leads without being held hostage to such concerns which are strictly irrelevant to the debate.
It also throws off by orders of magnitude the effort which would be required to fully model an organism neural behavior.