From what I can tell from a quick google search, China has over 1000 coal plants, and is building almost 200 more [2]. The fact that China is building 15 nuclear plants instead of 150 feels like they're only dipping their toes into nuclear, not fully adopting it.
And it looks like the US has about 50 nuclear plants, with only 2 more under construction [3], so they're doing better than us, but that's a low bar.
They are however also designing and building their own molten salt reactors and are building next gen reactors on the pebble bed design.
So I think that somewhat excuses their lack of scale for now as they probably want to get operating experience with these technologies before scaling much harder than that.
And it looks like the US has about 50 nuclear plants, with only 2 more under construction [3], so they're doing better than us, but that's a low bar.
[1] https://www.statista.com/statistics/859266/number-of-coal-po... [2] https://www.canadianenergycentre.ca/commentary-china-is-buil... [3] https://www.eia.gov/tools/faqs/faq.php?id=207&t=3