Pure speculation, but C# is not nearly the first class citizen that go binaries are when you look at all possible deployment targets. The “new” Microsoft likely has some built-in bias against “embrace and extend” architectural and business decisions for developers. Overall this doesn’t seem like a hard choice to me.
If you are a rust devotee, you can use https://github.com/FractalFir/rustc_codegen_clr to compile your rust code to the same .NET runtime as C#. The project is still in the works but support is said to be about 95% complete.
Cue rust devotees in 3, 2, ..