I'll take a crack at this. Elixir lays a really nice syntax, set of tools, and community over top of Erlang/OTP which are already amazing. While the language is new and increasingly popular, it is arguably not widely/well appreciated how nice and solid the language/ecosystem is at this point in its lifecycle.

Ecosystems grow a lot faster these days because there's tons of prior art.

I can feel that this feeling comes from perceiving hard-core FP perspective. I could be wrong :)