My opinion rarely resonates with HN because HN is full of programmers who are well into the top 5% of programmers. The last thing any of those fine folks want to hear is anything bad about their favorite language, be it Lisp or Haskell or Clojure or $SOME_OTHER_LANGUAGE_IM_TOO_DUMB_TO_USE.
I'm the dumbest guy on our programming team. I'm also the lead. My main service to the company is to try and keep the code base debuggable. I do that by limiting clever things as much as I can.
Haskell strikes me as very clever. It's sold as if it will produce less buggy code; I've not seen real world evidence that that is so and I highly doubt it is impossible to write bad Fortran in Haskell.
So perhaps the reason that Haskell hasn't taken over the world is that it seems to be something that "smart" people like and more average people don't understand. Any business that doesn't worry about how they are going to support their products (and hence their source base) down the road isn't going to survive very long. The rockstar leaves and everyone else starts rewriting his code.
This story is as old as the hills, it's been the same way ever since there have been programmers. A really great programmer can get the job done in any language and a true rockstar will write code that even I could understand.