You can still live comfortably on US minimum wage if your cost of living is like in China?

What question is this? With a US minimum wage with China CoL you are rich.

Definitely not in the major cities, like Beijing, Tianjin, Shanghai, and Guangzhou.

$7.25 minimum wage per hour at fed level. 40 hour per week and 50 working week you have 14,500 USD, or 105K RMB roughly based on exchange rate today.

105K RMB yearly is close to or above average even in the above cities.

for some state the minimum wage can be $15 or higher, this is wayyyy better than China.

It depends on where you are. Metropolitans and provincial capitals are expensive, but some smaller cities are cheaper. But then the public service is worse and you kinda want to live closer to bigger cities. I don't know how much $$ you are talking about, but it's easy to figure that out if you can give me a city in mind and I can check the cost for you.

Not just cost of living is lower, but standard of living is too. I know people in China who had full-time jobs but would recover meat from other people's rubbish to eat, or who lived illegally in a garage. That's homeless-level lifestyle for America and doesn't require any job at all.