HBD deniers think that they are debunking racial differences by constantly claiming IQ has a low heritability or that genetic variation has little independent effect on IQ. But if I were a racist, I would be literally dancing over the claims that IQ has low heritability because it implies that if there are racially genetic differences in IQ (and there are), these differences are very ancient & took an extraordinarily long time to evolve (tens of thousands of years), because the less heritable and independently genetically influenced a trait, the harder it is for natural selection to act on.
This would mean:
1) racial differences in genetic IQ are here to stay for the foreseeable future. No amount of eugenics or gene therapy will bring blacks up to the same genetic IQ level as whites anytime soon
2) low IQ high school drop out white trash can lord over Harvard educated blacks by saying “you might have a much higher IQ than me, but I have a higher GENETIC IQ. Since IQ has such a low independent correlation with genes, your genetic IQ will regress precipitously to the black mean of 85 while my genetic IQ will regress up to the white IQ of 100 and thus surpass you!”
3) IQ differences between social classes and between Jews and Gentiles would likely be almost entirely nongenetic. This is also good news for white racists since many of these are of lower class non-Jewish background.