Furthermore, once China reaches an equilibrium, they'll be producing less raw steel from iron ore and start smelting scrap steel. Its the expressways and high speed rail networks that have been the major consumers of steel domestically all those elevated sections, bridges etc use a lot of steel, and the bulk of those networks are done.
Thing is China already produces more steel than it consumes in fact it produces more steel than the next 20 steel producing countries, so there will need to be some restructuring, once domestic consumption drops further, that or ship it all stateside for Biden's 'build back better' pork barrel, gravy train