e.g.: is it worthlearning Python?
If you're going to do data science, probably yes.
(you can also do that with elixir with LiveBooks)
Is it worth learning Elixir?
If you want to create The Witcher 3, probably not.
If you want to do Android or iOS development probably not.
If you want to develop multitasking stuff, that requires multiple seamless integrated processes on different machines on a cluster or the backend of Whatsapp. Definitely yeah.
What about for web development? IMHO it completely replaces both React and Angular and you're faster with it.
For scripting it is also an excellent tool.