C was used because it existed 30 years ago, and is full of ambiguities (undefined behavior), and Rust curtails UB quite a bit by defining many semantics that ar

C was used because it existed 30 years ago, and is full of ambiguities (undefined behavior), and Rust curtails UB quite a bit by defining many semantics that are left unspecified in C. You don't need a "locked down" language to build an OS. In fact Linux just upgraded the version of C they use to C11. Time always marches forward, my friend.