It can be hard for me to tell whether the writer is making a racist joke I don't have the context to get, trying to be anti-racist and failing, or slipping into stereotypes without meaning to - or any number of other possibilities. But Wylie-Balmer seem to mean well here. For a book about elite scientist cabals thumbing their noses at the great unwashed mass of humanity (or solemnly shouldering the burden of survival on behalf of the species, if you like) it's surprisingly free of overt racism. It's not free of pro-eugenics sympathies, but so little was in 1932 outside of GK Chesterton (who definitely did not escape overt racism) and other cranks.

Anyway, I'm rambling. The point is, I too read too much old stuff. /o\ indeed.