This is assuming, of course, that the PRC value system and legal framework is lock-step with Chinese modern ethics, traditional ethics, or Chinese culture.
Whiiiiich of course assume that that's homogeneous, which, obviously, it isn't. Just like "Western morals" aren't (I'm trying to be good faith in parsing that and I can't figure out what you mean by western morals).
So when you say "The Chinese will be the ascendant ethnicity and culture," do you mean the rural American scapegoat? Aka, chopsticks, epicanthic folds, and Simplified Chinese? I could see how that could be the meat and potatoes of the argument, because even if what that actually ends up meaning in reality is that though a separatist Democratic movement overthrows the CCP, the (future) USA populist government successfully redefines the Chinese Threat to include this completely different political structure to fall under the umbrella of "Chinese," which society has allowed to mean what I'm arguing we should prevent it to mean.
I can say where you're completely wrong - it's not mildly humorous to find me in this position. It's fucking hilarious. Of all political considerations on earth nothing heats my blood more than the evils of Xi Jinping and the tyrannical PRC regime. They are bullies, they violate human rights, and they should be overthrown. I have to balance this against my love of all the good things that Chinese culture brings to the table, just by nature of being a bunch of humans with a rich ancestral background forming their language, food, traditions, etc. And by Chinese I again refer to that concept vague even in any of the languages that adopted the Chinese writing system.