For example, quite recently, several respected geneticists declared that there was no such thing as race - an idea that not even the dimmest kid I knew back in Detroit would have fallen for.

That struck me as a stunning nonsequitur. The kid in Detroit has no possible way of knowing how much of what they see is genetic versus environmental - unless they go online and read the scientific literature. Offering that sort of surface observation as evidence is on the level of "any kid in Detroit can see the Earth is flat".