There's some truth to this, but "can be optimized" is not the same as "there exists a compiler that optimizes".
Your statement gets repeated a lot (and similarly about the JVM: it has run-time information that compilers don't have, so can optimize better), and yet C++ and Fortran continue to come out on top.
Indeed, because C++ and Fortran get the money and time, and they're closer to the metal to begin with. Also, C++'s "Nasal Demons on UB" problem helps a lot.
But yes, OCaml is quite fast, and probably could be faster. Does it really beat C++ in all contexts? Probably not, but it's still pretty fast.
