Who are you grouping under auspices of "the Chinese people"? Clearly there are large groups of people within China who want nothing to do with the One China policy.
There is no telling what will happen when the economic gravy train comes to an end, especially if it were to do so in a jarring way. I suspect this is one of the reasons why Xi has become more authoritarian recently.
Can you expand on that? In particular, how that justifies governing those people against their will.
The rule-based global system is a relatively new thing. if you look back pass WW2, it is obvious without the United States as the solo superpower, it is barbarian politics between countries, not so much for "rule-based system".
Thus, what many really expect to see, when they think about national self-determination, it is envisioned as many smaller countries with one superpower, that is the United States, with globally projected military power.
That is certainly possible, but there are many questions left, for example, how that many smaller countries counter-balance the desire of the United States?
Alternatively, can the E.U. be an example? It is certainly possible as well, but we have to ask, at which point, the E.U. will act more like one nation, where is the boundary?
All these discussions are orthogonal to the authoritarian discussions. I am certainly sad to see people view the Chinese as unable to pursuit their own democratic process without breaking the whole country.
No, that is extremely unlikely. Not just unlikely, I would view it as pretty much impossible.
The motivation? A belief that humans are entitled to at least a modicum of political self-determination.
They want 1 hive mind, including religion
You must be talking about the Han people, certainly not the Tibetans or the Uighurs. Those clearly have separatist ambitions, but they don't have the power and the support to make it happen.
As for Taiwan, Hong Kong or Macau - none of these want to be united politically with the PRC either, even though they are mostly Han.
A soviet-style political breakdown could be the best thing to happen to the people of the PRC, considering that those smaller Chinese countries are very successful.