You could say it's central to their culture. Sort of goes for most Asian cultures, the education of children is something Asian parents will sacrifice greatly for.

Curious that education is valued so much, but then there are cycles of uprisings where educated people are targeted (Cambodia, Chairman Mao, ..)

It's a bit more complicated than that though.

As always the revolution starts from the competing elites. The culture revolution happened because CCP couldn't allow any form of alternative power centers.

That's pretty blatantly false. Mao had a very large number of China's teachers executed during the 1960s, which set the entire nation back two generations in education (at least). The teachers - along with many other enlightened peoples - were murdered for being so called Capitalist intellectuals.

Pretending "always" for anything related to China, you can be sure their elaborate history will prove you wrong.

Not democratized education, to my understanding. Rural china has never had the sort of broad access to education that exists there now (and is still rapidly developing).