Rust and C are the same "tier" of performance, but GNU coreutils has the benefit of several decades of development and optimization that the Rust one needs to catch up with.

@Strit @rezad Memory and thread safe yes. Performance was more roughly equal, could be faster or slower depending on use case.

Rust never claimed to be more performant than C. Its performance is equivalent to C.

Rust is fundamentally more limiting than C, even with unsafe. It is often faster if you write naive code (because the Rust compiler can optimize more aggressively due to those same limitations), but an experienced developer with a lot of time for optimization will probably be able to squeeze more performance out of C than they would out of Rust - as you can see in this example. Rust is still better because those limitations all but guarantee that the resulting code will be safer, and the performance differences would be negligible all things considered.

It's more a thing like in ripgrep vs. grep; new algorithms being vastly faster in most cases except in some.