People in China, at least those millions people who are able to cross the Great Firewall, know that democracy is generally good, but they also know that a strong central government can also be useful for certain circumstances. Most westerners and HongKongers on Hacker news have a very extreme political view, you just believe "democracy is good"(TM), protesting against the evil Chinese government is good. But can you take a closer look at what is really happening in HK and then decide what you believe?
BTW, I'm neither pro-protester nor pro-police, I think the protest is a result of economic regression in HK. You could also check my comment and posting history to see that I'm not a 五毛党.
The Chinese government survives for the same reason every authoritarian government has survived throughout history. Overthrowing governments is really hard and requires truly extreme circumstances. That's the core problem that democracy solves. Overthrowing a democratic government is as easy as checking a box on a form. Overthrowing an authoritarian government requires violence.
Yes and no. You're changing the representatives of the government, but the general circumstances are largely continuing. You don't see a large turn when a new government is elected in a democracy, which you would if it was "overthrown", imho. Similarly, you won't see a large turn in an authoritarian society if the president changes, because in both cases, "the system" remains the same, and changing the face of the system doesn't fundamentally change anything.