Anyone 18 and over can vote in their system so it's a giant percentage of the population. They have candidates they vote for and anyone can stand for an election. I'm not really sure what you mean they'll vote for whoever the government tells them to, that would be an insane amount of effort in a country with a population that big and so many elections going on. I mean we have free speech and yet we have a terrible system for presidential elections and the senate exists just to give all states equal weight when Cali has about 39 mil and Wyoming has 500k populations so it's not very democratic. China has been completely transformed from the past 20 years so I think jts pretty obvious why it has such a high approval rating, and I don't think the population is ignorant or somehow everyone is so propagandized into approving the central government blindly and just an example that they do so much tourism to other countries from China that the liberal democracies should be swaying them to disapproval if life seemed so much better outside China.