Earlier quoted context omitted.
If you want to learn a functional language absolutely do not learn Haskell. If you're interested in static functional programming, learn Elm and then F#/OCaml. If you're interested in dynamically typed then learn Clojure or possibly Racket. That's it. Spending time learning Haskell as your first (or even second) fp language is a terrible idea and has done more to slow FP adoption than anything. You can learn Elm lite…
Agreed. Haskell is masters class in functional programming that is generally more interested in pushing theory forward (not necessarily a bad thing). If you are a .NET developer, F# is a wonderful language (based on OCaml) that allows you to ease in to FP since it supports functional, oop, and procedural programming. Plus, you have the whole .NET ecosystem as well. You can become very productive, very quickly.
There is plenty of real-world Haskell code in production systems by industrial users.
The research is on practical applications.