I wonder whether the "replacing c in the linux kernel" is not more wishful thinking by Rust enthusiasts. As of know it has less than 1% and less than bash.

NetBSD puts Lua in kernel space, is it a C competitor?

Rust is an obvious competitor to C++, both are similarly featured.

When people talk about "modern C competitors" they're almost always talking about more minimalist languages like Zig, Odin, C3, Jai, Hare, etc...