Really good C++ programmers are often unwilling to give up the control and power (in practical terms) of the language + libraries. Any piece of code written in a higher level language can always be 'improved' upon / optimized in C/C++, while still remaining reasonably generic. This over time pretty much guarantees that 'timeless' code, like math and graphics libraries, ip stacks etc. will have their canonical representations in C or C++, with 'easier' languages simply linking to those, instead of bothering to provide their lesser own. Soo, those who want to write timeless code do it in C / C++, hard or not.

I think Haskell's appeal lies in being everybody's favorite local maximum, while remaining only a very select few's global one.