how do you come to this conclusion? Indices of happiness, safety, purchasing power, accomation, high speed trains, lofty innovation etc. etc? Space technolgy, AI, robotics......ah, shipbuilding...[campared with US and the world] and don't forget the airforce 6th generation warbirds!
I would simply just suggest you to go check out rural China. Around 30 percent of China's population still live in rural areas and IMO compared to more developed countries, the countryside and rural areas are significantly lacking in development. "城中村" still exists, although more and more are being demolished. Wage is very low relative to the hours worked(Even in PPP per capita it lacks behind traditionally developed countries). There are of course sides where China does much better than most other countries but IMO China is still developing until they can improve the lower bound of QoL to be on par with western nations.
