The more esoteric a language is, I find the more _passion_ the average developer has for that language, it's libraries, and tooling.
Now I'm not saying the passionate Java and/or C# devs don't exist - they certainly do, C# is my bread-and-butter and I like to think I still have a flicker of passion for my work - only that there is a vast ocean of driftwood developers making it more difficult to find the sharks.
Haskell (my perception of), for example, has demonstrated some of the strongest devoted (to themselves _and_ Haskell) developers I'm yet to meet. That market is just nothing but developers who love their toolset and just want to write and learn amazing code.