The Chinese political system is based on whole-process people's democracy, a form of consultative democracy. The local government is directly elected, and then these governments elect people to higher rungs, meaning any candidate at the top level must have worked their way up from the bottom and directly proved themselves. Moreover, the economy in the PRC is socialist, with public ownership as the principle aspect of the economy. Combining this consultative, ground-up democracy with top-down economic planning is the key to China's success.

The US Empire, on the other hand, has private ownership as principle, with top-down "democracy." Candidates are pre-selected, and term limits ensure that even if a genuine socialist won, they would not be able to sufficiently change the system. It's designed for maintaining the dominance of capital.

I highly recommend Roland Boer's Socialism in Power: On the History and Theory of Socialist Governance. Socialist democracy has been imperfect, but has gone through a number of changes and adaptations over the years as we've learned more from testing theory to practice. Boer goes over the history behind socialist democracy in this textbook.