The only reason Chinese companies can even get away with these big projects is because of state backing and state objectives. By itself, the market doesn't support a new general-purpose OS at this point.
Technically you are correct but the commenter you’re responding to means that with the amount of Western Governments spend on MS products and services, the are a d facto (if not de jure) state backed enterprise.
US government spending is (for now) easy to track, and you can get totals for spending by corporate entity.
In total across the entire US federal government, $518.8 million was paid to Microsoft for products and services in 2024. That is approximately 0.21% of their total annual revenue.
I assert that the threshold for "state sponsored" is well in excess of 0.21% of annual revenue.
How much money have states and local governments spent on Microsoft products and services? How much money has Microsoft collected from companies that are providing products and services to US governmental agencies?
Government spending is not easy to track. This doesn't even begin to touch on non-monetary benefits Microsoft receives with government influence.
MS has deep ties into the state department and intelligence apparatus that few other companies do. Just as deep as the defense contractors who have a near monopoly-monopsony relationship with the federal government. You can argue about how exclusive they are in particular qualities but the scale and depth they operate at makes their relationship approximate the relationship Huawei does with the Chinese government. They're just what state-backed enterprises look like under liberal-ish capitalism.
Besides, the statement's completely nonsensical - there were multiple OSes developed by for-profit corporations in the West (Microsoft, Apple, Nintendo, QNX, Be, etc.).
It's kind of an extraordinary statement that an OS couldn't be developed by a for-profit organization, especially if the hardware's somewhat fixed and you don't need to support every piece of equipment under the sun.
Actually the “market” won’t prioritize anything that won’t give returns as soon as possible (except for the weird situation of VC money being poured in).
It is a lot less if you are aiming to support a small set of platforms, don't need general driver support for everything possible accessory and peripheral under the sun, and if your file system usage is limited.
If you are building for a single abstraction, code gets much simpler, instead of building a platform that multiple abstractions can then be built on top of.
If you are China, the vendors are you and money is treated differently than in the west. Balance sheet will accommodate a project like that easily, especially if it decouples them from the US. They’ve already got their own software ecosystem which most people don’t hear about or heard once or twice, and it’s running their tech scene.
Geopolitical reasons for making your own OS are actually reasonable and understandable. Not saying they are good, because I would much prefer a planet where we collaborate on these things… but they’re not dumb. They make sense in a similar way the space race made sense.