The US may have effectively banned it, but everybody else is buying loads of it.

As far as I can tell it's operating at capacity. China's installing it for the same reason everyone else is. It's cheap as chips. Power stations take a lot of planning and management, while you can take a few acres of fields and effectively turn it into a money generator with no moving parts.

I'd have got some myself, but my house faced the wrong way to get in on the free solar panels boom, and the up front costs mean it won't pay itself back for like 20 years. I was tempted once the prices went through the roof when Russia invaded Ukraine, but I moved to a tariff priced every 30 minutes or so and the benefits vanished. I might as well let a local farmer build it all instead.

https://ourworldindata.org/grapher/electricity-prod-source-stacked?time=2000..latest&country=CHN%7EOECD+%28Ember%29

(chosen OECD because it makes the numbers easier to compare, and doesn't cherry pick EU countries which are actually better than places like the US)

A lot less coal, which is about twice as bad as gas for CO2 emissions per kWh.

Places like the UK have got rid of coal completely. The last remaining coal power station shut down last year. When you look at the graphs for the UK, we've actually reduced electricity consumption as a whole, despite a growing population and the growth of electric vehicles.

Still plenty to be done about gas. I can see why China still uses enormous amounts of coal. They don't really have any oil, so it's the cheapest fossil fuel they have access to. In fact, cost is mostly why solar is getting popular, because it's become extremely cheap. You can't rely on it completely though, unless we all agree to turn off our power at night. Power storage is not a solved issue by any means.

China also never embraced nuclear power. They really got big on the world stage right around the time Chernobyl happened, and it was already getting too expensive even then.