Not a particularly fair comparison though, as that C binary is loading dynamic libraries that are already in memory. Case in point: that C program needs the C standard library, but by default that library (glibc) is dynamically loaded. Rust is not offering the Rust standard library as a dynamic library, hence the larger size. Not to mention, interfacing with C functions in the kernel.

You'll get different results if you compile them with musl for truly static and fair binary size comparisons.