My observation was that to feel comfortable in Java I tended to require a very powerful IDE (Intellej) to deal with refactoring and appeasing the type system.
When I write Elixir, I feel comfortable using a much less powerful (from a language integration standpoint) Vim, mostly due to the constraints Elixir has in the language. In Elixir, there is no mutable state, I can feel confident that the only things affecting a function are the things in front of my face when reading it. Elixir's alias/import syntax make it pretty easy to jump to the file that has a function definition in.
I think FP languages tend to have an edge in how much power an IDE is required to have, because those languages tend to have features like immutability and composable higher order functions)