[mrdoops]

There's different kinds of "fast" is the problem.

Are you juggling lots of messages concurrently and orchestrating across complex topologies of nodes? A BEAM language is going to excel. That's why Whatsapp, Discord, and RabbitMQ use Erlang/Elixir.

Are you trying to go really fast in a straight and simple concurrency scenario? Go/Java/C++/Rust is going to be faster than a BEAM language in those scenarios.

You won't want to implement a complex concurrency run-time in Java whereas Elixir is not a good choice for a 3D game engine.

Still, there's nothing wrong with using both.