SBCL is fantastic, but the resources being poured in GCC and LLVM combined with CPU manufacturers including architectural features to help C and related procedural languages work better make it a massive uphill battle. I suppose that with proper use of things like sb-simd and arena allocation you can get in the ballpark of C, but with some tweaking C, C++, and Rust can get insanely fast (of course Fortran's better, but nothing compares to it, so let's leave that aside for now).