Because even in china they can't build nuclear as quickly (and likely as cheaply) as wind and solar. It's hugely different [0][1]. Over the last 10 years, they used 3.5x more energy (so not nameplate capacity, but actually generated energy) from solar and wind than they did from nuclear.

Further, if you download the data [1] an look at the derivative you get an even more grim picture. Not only is wind and solar increasing rapidly, but the derivative is positive (and possibly increasing itself). But when you look at nuclear, you find that not only is it not increasing as rapidly, but it's derivative is going down and heading for zero fast.

[0] https://cleantechnica.com/2023/02/06/renewables-in-china-tre...

[1] https://ourworldindata.org/energy/country/china#what-sources...