C# is nice, but it is nowhere near Rust in terms of safety or expressiveness. Thankfully they are finally adding discriminated unions (sum types) and other sorely missing features.

Unsafe in C# is much more dangerous than unsafe in Rust, precisely because it doesn’t actually color a function. It just allows its body to use pointers. This is why you have methods in the CLR called “DangerousFoo()”, and the compiler does nothing to prevent you from calling them.