Some things I have learned about China from others who know more than me that have been helpful in understanding why things are the way they are:
1) China has a history of authoritarian rule, punctuated by extremely violent rebellion. The Chinese government's biggest concern is avoiding the second of those things.
2) Though China's cities are first world, a large fraction of China's population still lives in third world conditions. China's government manufactures consent for its existence by transforming that third world economy into a first world economy. Being the world's factory drives that transition.
3) China's government has motivations to be a good trade partner (mainly, access to luxury goods the rich want and high-technology items like jets), but see #1.
4) China's advances have come at great environmental cost, and they have invested heavily in renewables. However, see #2.
5) China also has a xenophobic (thanks Japan, Great Britain), tradition-heavy culture that is difficult for westerners to navigate.
I was watching the recent JRE episode, with Elon Musk as the guest, last night. He said that China is actually surprisingly progressive on climate and the environment. He commented that they're much better than the US, but it's a fairly recent phenomena. He said something to the effect that China used to be terrible and considered climate/environment issues to be a silly thing that westerners worry about. However, they asked their own experts and they confirmed that it is a real thing. Ever since, China have made rapid improvement.