How imprortant is elixir in all this? Is it merely the frontrunner of a useful new pattern? E.g., do erlang, BEAM or functional programming play a critical role or will other stacks effectively replicate this and how are they doing so far, which would be the next more mature?
There is a port for Go: https://github.com/jfyne/live . However, the API is not nearly as clean and nice, and it's probably not as efficient as Phoenix either. But overall it's really made a number of applications much easier to build and it has allowed me to avoid mountains of JS.