Don't hear me wrong, I think Elixir is an amazing language and I love using it, but it has nothing to do with Ruby, the paradigm is completely different. It makes me think that the only reason Ruby devs are so into it is just because the syntax is similar, which make them seem a little... shallow I guess.
Elixir just came up on my radar and I started seeing a lot of smart people looking at it and Erlang, and so I did too. Now I kind of don't want to go back to Ruby. Part of it is that I like Elixir's syntax better than Ruby's, but mostly it's everything else.
Ruby isn't very good at concurrency, so people making Rails apps have to move things to other services (sometimes in totally different languages) in order to get around this. As I've learned more about OTP I find that I can spin up different 'services' in the form of GenServers that are running inside the same VM, use supervisors to handle the inevitable crashes that will occur, and because the entire system is in the same language/VM it's a little easier to test. So far it all just feels less like some Frankenstein that's getting stitched together. :)
Phoenix is nice too, but a lot of its niceness and power really comes from things lower than it in the stack: OTP, BEAM, Cowboy, Ecto, and mix. I really like Ecto so far, it feels more natural to me than ActiveRecord once I've gotten the hang of it, although it still has places where it is obvious that it's not quite as mature. One thing that Phoenix provides which is really nice (although I haven't made much use of yet) are the channels.
However I agree, very little Ruby syntax, just def & end for the most part.
Perhaps the history of Ruby uptake explains it? My feeling is many of these 'Ruby' developers started as Rails developers. Rails did cool stuff, but it had they fanboy/hype around it that only Apple usually garner.
I wonder if now Ruby is established, has lost its excitement, and problems are encountered by users day-to-day, Elixir looks like the next magic bullet? I.e. they are predisposed to being attracted to the noise [and NodeJS didn't attract them all because of...??]
I've nothing against Ruby or Rails, but I did not appreciate the single-minded hype and excitement around one piece of technology which wasn't flawless.
I would hate to see the same thing happen with Elixir which, I believe, can become an amazing technology and finally help give Erlang the recognition it deserves.