Final-Fan said:
If such cognitive differences exist, they are miniscule compared to, and completely obscured by, the natural range of intelligences and the differences caused by upbringing. |
The natural range of intelligences is a valid point, in the sense that a person of any race can be intelligent. It's just that there are differences in the group averages, so we can't expect identical levels of achievement across all races.
As for the differences caused by upbringing, it's far less significant than you think. From Wikipedia: "Various studies have found the heritability of IQ to be between 0.7 and 0.8 in adults and 0.45 in childhood in the United States."
https://en.wikipedia.org/wiki/Heritability_of_IQ#Estimates
Furthermore, there exists a racial gap in SAT scores (highly correlated with g) regardless of family income in the United States:

From the College Board's data, we can see that the poorest whites (978) have scores almost identical to the wealthiest blacks (981), something that cannot be explained by environmental theories.







