This viewpoint never made sense to me, because you have variation within any culture, and because advantageous strategies win out over time, any culture will evolve. Therefore, it never made sense to me to consider culture a static immutable group of homogeneous people. To me it is pretty obvious that some systematic challenges must exist that keep what we consider to be successful strategies from succeeding in those environments.

Your examples of Russia and Japan are easily explained by geopolitics. Indeed, Japanese individuals don't tend to excel out of Japan while many Russians do.

> win out over time

And people define victory in different ways. Having many children is how some people define victory. Having no children and a diploma on the wall is how some people define victory.