In every case, like the engineering team in this article demonstrates, the developer experience and end results have exceeded expectations. If you haven’t used Elixir, you should give it a try.
Edit: Fixed an editing error.
Unless someone who knows those three languages is curious or encounters a particular problem that motivates them to explore, they're unlikely to pick up an immutable, functional language.
I have never looked back.
Elixir is an absolute joy to use. It simplifies multi-threaded programming, pattern-matching makes code easier to understand and maintain, and it is magnitudes faster to code in than Java. For me, Elixir’s version of functional programming provides the ease of development that OOP promised and failed to deliver.
In my opinion, Elixir is software engineering’s best kept secret.
That's what I love about Elixir, but it means that selling it is more like convincing a developer who knows and uses CSV to switch to Postgres. There's a ton of advantages to storing data in a relational DB instead of flat files, but now you have to define a schema up front, deal with table and row locking, figure out that VACUUM thing, etc.
When you're just setting out to learn a new language, trying to understand a new OS on top hurts adoption.
As an example, we just rolled out a feature in our cloud offering that allows a user to remotely call a robot to a specified waypoint inside a facility, and show real time updates of the robot's position on its map of the world as it navigates there. We did this with just MQTT, LiveView, Phoenix PubSub, and a very small amount of JS for map controls. The cloud portion of this feature was basically built in 2-3 weeks by one person (minus some pre-existing code for handle displaying raw map PNGs from S3, existing MQTT ingress handling, etc.).
Of course you _can_ do things like this with other languages. However, the core language features are just so good that, for our use cases, it blows the other choices out of the water.