C# is much more capable and fitting this purpose today than 10 years ago (perf, codegen quality and infrastructure have improved by orders of magnitude). Howeve

C# is much more capable and fitting this purpose today than 10 years ago (perf, codegen quality and infrastructure have improved by orders of magnitude). However, it cannot compete with Rust when it comes to systems programming. Mainly because it has different tradeoffs and its high level abstractions and other features like LINQ, interfaces, non-struct generics and async/await are very much not zero-cost, unlike in Rust. In addition, it does not offer crucial features one would want in kernel development: deterministic memory usage, compile-time safety guarantees for writing concurrent data structures and general systems-programming-first language design. While C# is a perfectly viable choice for writing userspace OS components, applications, UI and etc., it is a bad choice for kernelspace when C++ or Rust exist.