If you take two genetically homogeneous groups and pair individuals from each group, what you get is not offspring that are halfway between, but are completely isolated from each other.
Suppose the two groups differ between groups on 1000 genes and within group are the same on those. Then a pair from each group will randomize the differences, so that they have 500 from each parent group. However, not the same 500. Each individual offspring is genetically distant from the other offspring.
The offspring of two races is not a race. It is a collection of separate races.
The separate races lack genetic similarity and homogeneity. Without shared genes, they lack the ability to overcome the Prisoner’s Dilemma.
Human Society is a set of tricks or protocols to overcome the Prisoner’s Dilemma. Genetic similarity is why these techniques evolved. Take away the genetic
similarity and the techniques will disappear as well.
Religion doesn’t survive without genetic similarity. It expresses the timeless sequence of generations. But in diversity that is lost. So the meaning of religion is lost. It is lost in Babble.
The city of many races is a soulless city of rules and cheating. Much like the modern Congress compared to those of 50 years ago.
Diversity brings down the greatest nation. First it becomes an empire. Then a totalitarian state. Then it flies apart.