I don't know, this has not been my experience with Haskell at all. Not only do plenty of people work on all sorts of libraries (there are some really great web frameworks, for example), but they also work on all sorts of "less interesting" stuff. For example, there are some people working to improve Hackage, which is the site that contains Haskell's libraries and their documentation, and Haskell has really good support in Emacs (which is much better than good IDE support!).
I haven't spent much time with Haskell lately but the last time I did Cabal was still way less polished and useful than Ruby's gem system or even Python's pip/distutils stuff. Robust, easy to use package management is step one in getting any new language off the ground, IMO.
