What makes you say China is anywhere near as corrupt as the US, or corrupt enough to not be preferable over the US? Combatting corruption has been a core part of the PRC's Political Economy over the last couple decades, combined with improving living standards, this has led to more Chinese citizens being more hopeful about where their country is headed.

I don't know China to be corrupt.

Oligarchist corruption specifically privatizes profits for social losses. Destroying/diminishing country is a sacrifice they are willing to make. But sure, bribery for foreign imperialist privatization is just as bad.

I'm guessing because oligarchic corruption is what's most effective at getting the state to work against the majority's interest. Small time corruption where you have to insert coin here or there to get things moving but you don't get power over the state can't do that. It only introduces inefficiency. Oligarchic corruption gets the state to represent the oligarchy's interests and since those are in contradiction with the interests of the majority, the states stops representing it. That includes taking control of any form of democracy that may exist. In the US the oligarchs have obtained control over the state and the democratic system. It's why there are never good options to vote for, but turd sandwich or a giant douche. I don't know enough about China but there are signs that the state is not owned by its oligarchy. E.g. when Jack Ma wanted to make a private bank / payment system that isn't controlled by the state, he took a vacation for a while and returned a changed man.