The collapse of the Eastern European socialist countries 30 years ago is an excellent example. But it only works when the general public had suffered enough and isn't willing to support the regime anymore. And the economic situation needs to get worse for one or two generations, it won't happen overnight and in a working economy. A few dissidents "speaking up" to incite change is a romantic idea, but it's not enough.
It's a kind of miracle it happened in most these countries without bloodshed. You need to mobilize large parts of society and have a favorable political situation to perform a coup like this without a civil war.
Yea, I meant in China but those examples you provided definitely illustrate how unlikely it will be to happen in China. It's pretty sad and I can't imagine having such a bleak future, especially for those that are more oppressed than others over there.
