The key word in the article is "again"
'Valve correcting again the Steam China numbers.'
This seemingly is a common problem with the Steam Hardware Report, with Chinese users being erroneously represented. It constantly gets fixed, although takes a bit. It could be the hardware surveys are sent out at a different time compared to the rest of the world, then combined in the following month.
This is proven by "Ended 2025 at around a 3.5% marketshare, dipped a bit in January, and fell to 2.23% in February."
It's because of the Chinese user influx during their holiday season. Valve is not correcting anything they are just showing the data. As usual, Phoronix is misinterpreting what they're looking at.
The other aspect I find interesting is the February spike in win10 usage, presumably from Chinese users. Where will they migrate to over the coming years as support goes away. They seem to be both resisting win11 and resisting linux perhaps as either it's not suitable for the games (online?) they play or not great for Chinese users, or perhaps along with the nvidia spike because of getting more out of those GPUs on windows.