China is kind of a slum, still. Any Westerner with a mostly positive outlook on the country has unknowingly consumed mostly CCP propaganda. Like having your entire image of everyday life in the USA sourced solely from mainstream media, but worse.
I would bet against China or India or any other nation rising to take the place of Europe or the USA in global politics. The underlying causes for why the world looks as it does now are mostly down to genetics and those haven't changed and won't change easily. China might have a higher average IQ and that does give them a huge edge, but you also need certain character traits to avoid corruption dragging the entire system down.