One could argue that Erlang/OTP has had decades to be used at work, and no one wanted to (sadly). Elixir taking over doesn't affect Erlang because Erlang wouldn't had become more popular over time anyway.
I personally am doing BEAM now mainly because of Elixir. It's undeniable that a "hip", and let's face it, young, crowd, having chosen Erlang/BEAM, gives it a big breath of fresh air (this is NOT to insult the experienced Erlang devs - it's just a fact that a new young crowd choosing your tech is an endorsement). Interestingly though, I'm more and more intrigued by the underlying technology. Personally I am not a fan of some of Elixir's design choices f.() versus f() for example, and maybe, just maybe, I'll do Erlang now.
Overall though, it was a total blast the other day to just run 10 000 processes so easily, within milliseconds, and watch all my cores go to max without messing with threads or even the (somewhat obtuse) Go channels. Actors really are easy to reason about. I like this model so much that I'm even looking at it for C (C++ Actor Framework).
I'd be interested to hear about your experience with the C++ Actor Framework. It seems like without the larger ecosystem of Erlang/BEAM for fault tolerance CAF is just a nice coroutine library.