This reminds of how the politburo of China is often made up of engineers, chemists, and people with similar backgrounds. Whereas American politicians are all lawyers.
The newer generation of leaders is mostly lawyers and economics degrees.
Source: https://foreignpolicy.com/2019/07/04/chinas-overrated-techno...
Presumably, there's also a very strong selection process to make it into the top ranks of this political system, that will have a very strong effect on who gets there and how they get shaped on the way - not mentioning the forces within, once you're in place.
So while it would be wrong to say the initial background makes no difference, I wonder how much influence it still holds once you make it into the politburo.