The Chinese had a big advantage in a lot of young cheap labour. But now the population is aging, the wages are going up and the playing field will level out.
They are also having issues with cheap capital. A lot got misallocated into building too many tower blocks and Xi's people don't seem quite as smart as dealing with it as Deng's were.
Deng was weary but willing to play ball. The generations after wanted to get rich as quick as possible, and lost some of that weariness. Xi now has to find ways dial that back without provoking a backlash or tanking the economy.
A lot of capital also fled, aggressively, to N America. There is a reason why housing in Vancouver is so insane...
They are also having issues with cheap capital. A lot got misallocated into building too many tower blocks and Xi's people don't seem quite as smart as dealing with it as Deng's were.