The blatant and undeniable fact that different racial, ethnic and other groups have had radically different economic and intellectual achievements for centuries, in countries around the world, has led to widely varying theories and widely varying political and other reactions.
A hundred years ago, during the Progressive era in the United States, the dominant explanation was that different genes made different races either more capable or less capable. Similar views prevailed on the other side of the Atlantic, among people on both the left and the right, many of whom urged eugenics, in order to prevent "inferior" groups from reproducing.
The problem with this explanation was that it ignored the great changes in the relative positions of races over the centuries. In medieval times, Europeans could not match the achievements of the Chinese, but in later centuries their relative positions reversed-- and there was no evidence of any fundamental change in the genes of either the Chinese or the Europeans.
Much was made of the fact that, within Europe, "Nordics" were prospering more so than the peoples of Mediterranean Europe. But, a thousand years earlier, the reverse was true. A 10th century Muslim scholar pointed out that the farther north you go in Europe, the more pale the people become and the "farther they are to the north the more stupid, gross, and brutish they are."
However much such words might be dismissed or condemned today, there is no reason to say that these words were untrue as of the time they were said. So many things that have been said about race may have had some basis as of a given time, even if the sweeping conclusion that these are immutable traits does not stand the test of time.
Today's racial dogmas are no more realistic, when they try to dismiss or downplay behavioral and performance differences among racial and ethnic groups, blaming different outcomes on the misdeeds of others. Nothing is easier to find than sins among human beings. But the fatal misstep is to assume that those sins must be the reason for the differences we see.
The more fundamental question that almost never gets asked is whether there was ever any realistic basis for expecting different racial, ethnic or other groups to all have the same skills and orientations, even if they all had the same genetic potential and there were no injustices.