Historically China has cared much more about security than the economy. Ming fought for 100+ years against the Mongols to permanently cripple Mongolia and secure the throne against the Mongol claim as Northern Yuan (which worked) and even went bankrupt fighting Japan rather than allow them to keep a foothold in Korea.
Just like threats for the Ming came from the north and they invested greatly in eliminating pretenders to the throne from that direction like Northern Yuan, China's threats come from the sea today, and there is significant investment in eliminating pretenders to the throne from that direction...
If China plays its economy management cards decently, a limited war with US/east Asian threats would supercharge the economy further.
The "problem" if you can call it that is that the west has now put total sanctions on China (to the level they can afford without starving themselves at least) is that there's now no economic incentive for China to cooperate with the west. Much like after Lin Zexu removed much of Britain's trade rights, any possible economic effects on the British for going to war effectively were annulled.
Either way, before the "war" begins, there might also be a partisan/terrorist destruction operation inside Taiwan so as to make the best possible starting position against US in a real war later. That would happen independently from the actual Greater Asia war, or as part of it, depending on how things pan out on both sides, and of course if the KMT will call for a new offensive against the PRC in the meantime.
