> More generally, I'm still waiting for a massively successful piece of software made in a language that would involve no mutation, no null pointers, only one numeric type, etc. Even John Carmack has not yet delivered a revolutionary game engine programmed in Haskell.

One can program with mutations in Haskell, and all the side-effects can be kept "sandboxed" at the same time; also I believe the side-effectful parts of a Haskell program can be compiled (in principle) in a way that results in very efficient code, as fast as e.g. C++, though I'm not sure how well current compilers are doing in this respect.

So in a way, Haskell (as a language) offers the best of both worlds.