I disagree that they could be number #1 in any way. I I don't think they can hold it together. Most of their population is aging, there isn't a large young population to replace the older generation. Secondly you have the gender gap which skews the dating market there, which leads to an insufficient production of new people. You also have corruption and weak leadership, a complete homogeneous population with a system that brainwashes them and turns them into robots with little capacity for broad thinking. You have bigotry and greed at a basic level which simply taints your reputation and the workings of the government. You have a tiny minority that holds all the wealth while the rest of the population lives in poor conditions. There is no Chinese "dream", people around the world don't aspire to go to China or live up to any Chinese "ideal" and create new things. China is surrounded by neighbors that it doesn't get along with it Singapore+India+Russia to an extent+Middle East+South Korea+Japan+league of South East Asian countries+U.S+Europe+African countries doing business with China. Its shown several times that it has an extremely weak corrupt political leadership, several CCP members were caught in Las vegas spending Chinese tax dollars. Culturally its insignificant, as I've said there is no Chinese ideal, so it has no "soft" power like the U.S does. Chinese people are universally looked down upon and they are rated the least physically attractive race of all races as well being the worst tourists. They haven't really contributed anything to global culture or invented anything new and set frontiers/boundaries like America did. You have ethnic tensions with Uighurs and Mongolians, the whole Uighur debacle is straining China's relationship with Turkey, another possible power player in the future.

Lets put it this way, if the U.S were to do something about the Chinese pegging U.S currency, impose tariffs on all foreign made goods and products, the Chinese would be completely screwed. There system would fall apart instantly. There are already ghost towns and railroads falling apart in China, not to mention traffic that lasts for two days.
Its entire industry is set in manufacturing and its shown poor abilities in innovation despite whatever progress they have made. Regardless of how powerful China's ground army is, its navy sucks, the troop technology and distribution is terrible. All of its recent technology has been stolen from the U.S which further proves my point that they aren't innovators. Its Olympic team was caught doping providing questions as to whether their Olympic performance was illegitimate and a political ploy. I really really don't think China's going to hold it together.