The guy is simply honest and clinically impartial.
Nowadays it seems that's a crime.
In grad school my major professor knew, and was heavily influenced by, Carleton Coon, and so I was exposed to his writings.
Highly recommended. The style is first half of last century; lots of data and a good, reasoned approach but not PC.
He was even-handedly "non-PC" with all the racial types.
I wasn't offended by the Irish bits so I have no idea why anyone else was offended by their particular chapters.
I found it fascinating.
Recently it's become fashionable to postulate that the Neanderthals did not "die out" but [genetically speaking] walk among us today.
This guy said that a nearly a century ago....without the benefit of mitochondrial [or any type of, really] DNA testing.