An odd assertion, given that nothing of the sort happened in the United States, which has widespread civilian arms ownership (unlike China) and various openly active dissident movements, including the militia movement, which enjoy substantial sympathy within the military and local police.
But the US has avenues to which to express dissent and seek redresses, such as an effective legal system and a mature civil society. China has none of that, which means the only way to express dissent is through violent means. That's why China's own official figures indicate it spends more on "preserving stability" at home than on its military. The leadership fear their own people more than any foreign adversary, and allocate funding accordingly.
This is what happens when an economic collapse happens to a long-standing dictatorship:
https://en.wikipedia.org/wiki/May_1998_riots_of_IndonesiaIt doesn't seem like a 2008 with Chinese characteristics is being forecast by many, but it seems the reason for this is just that Evergrande is more isolated from the rest of the economy than Lehman Brothers might've been (although how this could possibly be true makes no sense to me), not because the likelihood of revolution is greater in China than in the United States.
https://www.reuters.com/world/china/disgruntled-china-evergrande-investors-crowd-headquarters-protest-2021-09-13/With more than $300 billion in liabilities, the developer has become one of the most systemically important companies in China. On top of its obligations to WMP investors and bondholders, it owes about $147 billion in trade and other payables to suppliers and received down payments on yet-to-be-completed properties from more than 1.5 million home buyers as of December.
