Learning it is challenging but achievable by most interested programmers. It's vastly different than most mainstream languages so it's not as easy to pick up as C# is to a C++ programmer because so few concepts translate from C++ to Haskell. But it's not impossible if you're seriously interested.

You also don't have to learn all of it to start using it. The majority of code I write in Haskell doesn't use anything more fancy than function composition, ADTs, and some type classes. You can do programming at the type level but that's not a requirement for entry.