Only part I disagree with is that, US will not be weaken that easily. In any near term war (2020s to late 2030s), they have significant chance of winning a conventional war with China. Yes, US will have significant losses. But China wont be able to stand on it’s feet for another century. To make sure of it, US+their accomplices will force unequal treaties on PRC as they had done with Qing Dynasty era China.
US hegemony will not only further strengthen across East Asia , they will also be able to focus on other global issues like Middle East , Ukraine . ( IMO, they will go after India, it is a possible Superpower of the distant future. They wont make same mistake of not containing China in 1990s- early 2000s)
For China to avoid this fate, they will really need to buy more time. If it has to fight a war with the US and it’s accomplices, they better do it in the near late 2040s or 2050s. (IIRC, Original goal of Beijing's world class military was around 2049) . Hide your strength, bide your time still applies.
I'm afraid you don't realize what warfare between two superpowers look like. It will be a repeat of WW2 but on an grander scale. Which means it will be a war of attrition, logistics and production. Even if we assume US is utterly superior to China in military competence and China is completely corrupt, weak, disorganized, they still have overwhelming number of missiles, planes, ships which are modern. They also have overwhelming capacity to produce steel, aluminium, chemicals and everything needed to continue build more weapons and ships and planes.
So, no matter how awesome US is and how bad China is when it comes to making war, US will suffer, massively. US will most likely lose their entire current standing army, navy and air force before they can attain any kind of "victory" and will be forced to radically mobilize their entire country and vassal states to produce weapons and provide soldiers. I don't even know what this victory even looks like. Because there is no way US can ever really invade China and force it surrender.
US at ww2 was able muster a force of 12 million at its greatest extent. That was when population of the US was 140 million. Now China has 1.4 billion people. They can easily muster a force of 120 million if they want. There is no way you can force such a force to surrender.
The only possible victory I can think of is some kind of ceasefire.
The sacrifice that is required to keep US hegemony in tact in asia after fighting such a devestating war will break the will of their people to further sacrificing for the sake of hegemony. Its how british broke their back after fighting ww2 and simply gave up on all the colonies.
That's assuming US wins and China loses. But the chance of that happening in China's home turf is extremely low. Cause I know china is not incompetent. Chinese are good at logistics, they are good at building massively and also organize for large scale tasks. So, if there is a war, it will be a victory for China, even after massive sacrifices and losses.
But as I said, its not about who wins or loses. US hegemony is gone whether they win or lose. They will break their back to fight such a war and others will take advantage and make massive gains in other regions of the world.