Per capita GDP China is still far behind US, but China is catching up, besides, China prospered for less than a decade, people still need time to digest what China is like now, this will take some time. Another important issue is China's not friendly policies to foreigners, it's extremely hard for foreigners to live in China long term, and China doesn't naturalize non Chinese citizens.
China is only for the Chinese. USA is for all the world. Big difference.