Very good point! I did not think of this at all. Perhaps the collapse of the Soviet Union discredited the planned economy as means of social equalization and they never quite regained their footing.

If I had to analyze the root cause of it though, I'd say the proximate cause really is Cultural Hegemony. Pretty much every piece of media and every interaction you have assumes liberal economics so much that it is very hard to even realize that you are working within that framework. An unknown known, kinda.