Mao did rid of the meritocracy-based education system, replacing it with an identity-based system. That is, if you were born with the right identity (blue-collar worker, peasant (not farmer, mind you), and soldier), then you get to go to a university without even any test. If you were born with the wrong identity (the right, the anti-revolutionary, the farmer or any family who has property, the "rich", the "bad"), then you can't go to any college. The results? Just look at China in the 70s. What a fucking hell hole.
As a for Stalin or Soviet, they never gave up their elite education. In fact, elite officers had to be elite students as well. Those who are good at STEM could even get a little leniency when they made the so-called political mistakes.