Why panpsychism isn't a solution to the mystery of consciousness

I have been reading an article by my philosopher friend Russell Blackford on panpsychism.

I take a stronger position on panpsychism, which is that it is simply false: There is a fundamental logical mistake with panpsychism, assuming the acceptance of "causal closure", that the brain is physical and all events that take place in the brain have physical causes. If all events in the brain have physical causes then those events are solutions of equations which enumerate physical laws. This is true in principle, even though such solutions may be intractable. Those solutions, by definition, cannot contain terms which incorporate panpsychism, because, if they did, panpsychism would be part of the physics of the brain. Therefore, it's not logically possible that any assertion we make about panpsychism can be because of panpsychism. Whatever the supposed mystery of mind is, that mystery cannot have panpsychism as the answer.

There are more subtle arguments against panpsychism, but the lack of causal effect on the brain is, in my view, the strongest.