We finally observed signals of selection for combinations of alleles that today are associated with three correlated behavioural traits: scores on intelligence tests (increasing 0.74±0.12), household income (increasing 1.12±0.12) and years of schooling (increasing 0.63±0.13). These signals are all highly polygenic, and we have to drop 449–1,056 loci for the signals to become non-significant(Extended Data Fig.10). The signals are largely driven by selection before approximately 2,000 years , after which tends towards zero.
That's the part that the speech police is afraid of.