Let me take your point even further: it is some principles of functional programming that make these languages a great fit for "refactoring" and "breaking apart

Let me take your point even further: it is some principles of functional programming that make these languages a great fit for "refactoring" and "breaking apart the monolith". Myself I'm more into Haskell. I see similar benefits in both Haskell and Erlang. A nice thing of Erlang is that you have to structure you application as a bunch of services from the start.