There’s already an OS completely written in Rust called Redox. Nobody uses it. I’m not entirely sure you could do useful work with it, which is contrary to the Rust marketing team’s talking points that Rust code is guaranteed to be fast and guaranteed to be bug free because Rust is just so darn great and the compiler authors so wonderful and smart. That there are basically no success stories other than a couple side projects after a decade of marketing is of no consequence.
Don’t read the blog posts. Go to the repositories. Check out the crates.io landfill. Grab the Rust book and try to write anything more significant than a CLI toy. I promise that you will know exactly why nobody uses the language in anger.
The Fuschia team, who are partly responsible for the Rust myth don’t even use it in their kernel. But they want it in Linux. I wouldn’t be shocked if this was all some conspiracy by Google and Microsoft to make a personal computing unusable so that everyone has to use their cloud offerings.