> Life in many authoritarian states is fine for most people. It is what it is; if you don't make a fuss, you can live pretty comfortably. Obviously many dictatorships are not like this, but China is fairly stable.
I've always found Chinese who left are either rich or not. If they're rich, they've seen other rich suddenly fall out of grace, suddenly "relocate" or outright disappear.
If they're not rich, they've always been miserable in China, and don't want to go back.
Well, most are not rich and the biggest complaint is hukou, ie. that you can't actually live where you want in China. The state assigns you a city and you go there. There's a huge set of consequences if you don't, and a lot of people aren't happy with the choice made for them. People outside of China think China is like the US. You want to live in, oh, say Washington, or Anchorage, you can just go live there, find a job and live life.
Which also means your basic question is kind-of wrong. There's a lot of Chinese who want to leave but can't. The only Chinese who actually leave were asked by the government to leave, for a purpose (often studying), usually only for a limited time. Now it's not like it's 100% forced, they do ask for volunteers and what you want but it's certainly not a free choice to leave China or go back.
In China you're effectively locked into your city/town/village, and often a specific building and job (you can leave for a weekend or ..., that's not usually a problem, though sometimes it is)
For the rich the fear is kind-of the same, just with much more pressure and much more consequences, essentially being asked to relocate, give up a company (apparently much more common under Xi), forced to hire someone and give them a high position, buy or sell certain things, and being arrested, even tortured (in some kind of torture chair) if you are even suspected of not complying with often corrupt requests from government officials. The issue with that is just how many corrupt governments or de-facto governments there are. State, province, city, 1000 special purpose governments (e.g. one for the coal industry). Of course, the state can't be bothered with having a standard for identifying/authorizing themselves, so there's scam requests too. Then there's the local police, and 10+ police services that all operate where you live for one reason or another.
Makes you wonder. I always thought a communist state would be like a gigantic bureaucracy. And it is, but it's also a mafia.
Second complaint you keep hearing is about the consequences of failing the Gaokao, or even succeeding but getting selected wrong/not what you want. There are no second chances.
And I do get almost all of Asia is less "do what you want" than the US or Europe is, but some aspects of China are absurdly controlling.
I've always found Chinese who left are either rich or not. If they're rich, they've seen other rich suddenly fall out of grace, suddenly "relocate" or outright disappear.
If they're not rich, they've always been miserable in China, and don't want to go back.