It didn't take nearly that long to see profound changes in the Soviet silver fox domestication experiment. How do you account for that?

I should have clarified that this general rule that it takes 1000s of generations for morphological change to manifest in our species applies only to natural rather than artificial selection (i.e., selective breeding). Obviously, morphological change can be created in a species in as few as a single generation via artificial means.

I also think there is no doubt that genetics can play some role in human psychological traits.

Indeed they do. Human genetics is obviously necessary for human psychology. No other species is capable of abstract/symbolic cognition like we are; this capacity is due to our unique genetic makeup. However, while genes allow for psychology, there is no reliable scientific evidence that specific psychological traits have some particular, consistent genetic basis. The available evidence indicates that genes merely have a general potentiating role in psychology and do not determine or even "influence" specific outcomes.

I suspect that genetics play a major role.

Why is that?