Shockley's contention was "that the major cause of the American Negro's intellectual and social deficits is hereditary and racially genetic in origin and, thus, not remediable to a major degree by practical improvements in the environment."
The Flynn effect shows that to be incorrect. https://en.wikipedia.org/wiki/Race_and_intelligence#Flynn_ef... . "The importance of the Flynn effect in the debate over the causes for the IQ gap lies in demonstrating that environmental factors may cause changes in test scores on the scale of 1 SD. This had previously been doubted."
Furthermore, "A separate phenomenon from the Flynn effect has been the discovery that the IQ gap has been gradually closing over the last decades of the 20th century, as black test-takers increased their average scores relative to white test-takers."
These show that if IQ tests are a reasonable measure of intellectual ability then there is a strong environmental component - far greater than what Shockley concluded. In other words, Shockley was wrong.
This is in addition to the multiple threads of research which concluded that a race assignment like "American Negro" has little to no genetic basis. Quoting https://en.wikipedia.org/wiki/Race_(human_categorization) as a starting point:
> By the 1970s, it had become clear that (1) most human differences were cultural; (2) what was not cultural was principally polymorphic – that is to say, found in diverse groups of people at different frequencies; (3) what was not cultural or polymorphic was principally clinal – that is to say, gradually variable over geography; and (4) what was left – the component of human diversity that was not cultural, polymorphic, or clinal -was very small.
> A consensus consequently developed among anthropologists and geneticists that race as the previous generation had known it – as largely discrete, geographically distinct, gene pools – did not exist.
So again, Shockley was wrong.
Since intelligence really does have a strong environmental component then Shockley eugenics goals (He "proposed that individuals with IQs below 100 be paid to undergo voluntary sterilization"), would have resulted in the disproportional removal of the gene lines of black people who, were it not for environmental reasons, would have had above average intelligence and thus be a benefit if the goal really was to breed for better intelligence.
That is, "certain desired traits" like intelligence are not as easily measured as Shockley would have us believe, and certainly not to the point where it can be considered "mechanical."
It's just all the social ramifications that are horrific.