IMO conflating air polution and greenhouse gases does not make a lot of sense. CO2 has the highest impact greenhouse gas, yet it has no adverse health effects in the concentrations humans are exposed to it. In terms of CO2 emissions per capita, China is AFAIK still below EU average and 3x below the US who is by far the worst offender among highly populated developed nations. Air pollution is a problem, yes, but a different one than combating human induced climate change.
I’m not sure where climate change enters the picture in this story. I don’t think China is investing in electric buses to reduce CO2 to head off climate change, but rather to control actual smog/air pollution.
