Something interesting I just found out is that China has even stricter emission standards for cars than Europe.
From left to right: China 5, China 6a (current), Euro 6d (current) and China 6b
From what I've heard, China 6b will be implemented in 2023, or maybe delayed a couple years. The biggest problem with it is that the particulate standards are incredibly high and will require cars to install a particulate filter, which will reduce engine power and cause heating issues for turbos.
Personally I think this is too fast. Chinese auto companies are still uncompetitive in terms of engines and this move could kill a lot of companies, even more than the current slaughter of companies like BAIC, FAW, Dongfeng, Brilliance, JAC. Other than BYD and maybe GAC, all the other companies are not transitioning fast enough to EVs. This move could kill them before they make the transition