This is an incorrect conclusion:

> In other words, the next generation will genetically regress to the mean.

Mating is emphatically not like mixing paints.

> [T]he Hardy–Weinberg principle, also known as the Hardy–Weinberg equilibrium, model, theorem, or law, states that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences.

https://en.wikipedia.org/wiki/Hardy%E2%80%93Weinberg_princip...