East Asian countries are just developed but have a mental block against mass immigration.
Mass immigration causes the issues it does in Europe and America because they run on a racial hierarchy, and the poor huddled masses are understandably not thrilled about being 2nd class citizens. On the other hand, they can also not return to their countries which were destroyed by the west.
In theory time might be on America's side, if they had the same level of administrative efficiency and population integration as China. But in practice, despite how much China is suffering from economic issues, America is still unable to exceed or in most cases even come close to China in growth.
This will only get worse with time for US because as the economic gap grows, 5% of growth for China will be way more than 5% growth for US.
Even if China slows down to a permanent 3% crawl due to demographic issues in the late 2030s, US would still need to grow at 5-10% just to eventually hope to catch up. And it was many decades since US had growth on that level.
There is just no way it could happen unless massive sweeping reforms happen in America while massive sweeping regressions happen in China. Time would only be on America's side if America and China switched governments.
The US grows 1.4% this year and China 5%, in GDP, even after all that covid bullshit and China getting the worst birth rates in history.
China could accept mass immigration if she wanted, it's just that she doesn't want that. She doesn't want to be an ethnically, and racially, divided country like the US, where civil unrest might happen at any time. China could immigrate all the SE Asia if it wanted due to its economic power and standard of living especially in large cities but China doesn't want that. The division is a weakness. China values its Han ethnic unity the most. That's why Chiha is so much faster than the US in making decisions in following them amongst other things.
China's immigration is migrating those 500 million more people from rural to urban areas and educating them more, increasing their productivity levels. That alone is enough for China to grow 3-4 more in real terms than the US for another 20 years. And by then, Chinese AI will work for them. China is already the leader in AI adoption, robot density, and whatnot.
Not to mention how CCP could introduce women to have children in their social credit systems with both benefits and penalties.
And it's not like those low-IQ immigrants help the US in any way, they are just a huge social burden above all, not a very productive force.