What exactly is produced in China that can't be produced elsewhere? The only thing I can think of is rare earths at cheap cost, since no one else is willing to pollute their environment so much with the lack of environemtal protections needed to achieve that. Then we have the whole QR payment systems that can't really exist without the lack of pervasive credit card infrastructure.
China has lots of labor resources, they have developed supply chains that have been left to rot elsewhere, but those can be ressurected relatively quickly if the need arises. They still have no modern fabs to speak of, and can't build a decent jet turbine or avionics for their own aviations efforts.