[jwr]

Practicality. Most of language "comparison" discussions miss out on the practicality aspect: does it work, does it have a good runtime (both true for Elixir and Erlang), can you write code that runs both client-side and server-side, are there good abstractions and libraries for many programming models, is it being actively maintained and developed?

Clojure ticks all of those and more, while most superficial comparisons concentrate on superficial aspects.