IMO, anybody who takes Charles Murray seriously needs to be hit upside the head with a hardcover of Stephen J. Gould's The Mismeasure of Man, which exposed race-and-IQ studies for the racist bullshit they are in the 1970s, years before the publication of The Bell Curve.
Its incredibly socially awkward to float the idea that you could judge someone’s intelligence by their physical features and claim some objective validity. This is quite unfortunate because in my opinion IQ is pseudoscience and intelligence is socially constructed, so its not going to be possible to substantiate that view. But since we can’t even propose such an idea for purposes of argument without the danger of social sanction, those ideas are never properly debunked.