I think there is a lot of disagreement about what 'learning' means and how long it takes. I while back I got curious about Elixir. So I downloaded it, skimmed the documentation, worked through a couple of tutorials and wrote a couple of trivial things. Took me half a day. I now feel I have a pretty good feel for what Elixir is and what its strong points are. Absolutely doesn't feel like a waste of time, even if I never write another line of Elixir in my life.