I agree with you that McLaren is referring to well-established cognitive science. I do, however, think you are wrong is saying to "extrooper" that he "can't think." Disrespect just leads those who resist challenging their own biases to dig their heels in even more. Evolutionary psychology supports the proposition that we are most invested in our own status, even at the expense of our own material well-being. Insults, even if based on truth,  beget spite, not understanding.