People act surprised when a compiled language approaches C performance. I don't understand why. Any language that compiles to machine code, doesn't store ever

People act surprised when a compiled language approaches C performance. I don't understand why. Any language that compiles to machine code, doesn't store every object on a GC heap, and has C-like function call semantics should be bound by the performance of its optimizer and not anything inherent in the language. Nimrod transpiles to C so it gets the C compiler's optimizer. Rust uses a LLVM backend so it gets the LLVM optimizer. It should be surprising if these languages don't approach C performance.