It is easy to gain huge percentages of momentum (if you could ever measure that) when you have little to start with. That's the case with Elixir. That's the same situation languages like Factor and even Haskell saw seven years ago. The former is more or less dead and and the latter still never "broke out".
When Elixir is competing library-wise and ecosystem-wise with the likes of existing languages like Python, Ruby, Java, Javascript, and then some of its major selling points are in competitors like Go (though not 100%) or Clojure/Scala (which can leverage the JVM), it really, really has to distance itself.
As great as Elixir is, it is hard to make a bet on it ever crossing the threshold of "this is really cool" to something you can goto because library x y and z are available.