The claim is huge. The story doesn't quite say how much is really about Elixir and how much from the revised architecture. That being said, going for something like Elixir has definitely an impact on the architecture... could it be that it pushes for better patterns?

Nice little primer about Elixir and Phoenix. Be careful though, I spotted a couple of mistakes in the code examples. That still gives a good idea of advantages and limitations of this stack.

This is clearly getting more mature. Even the list of issues presented here actually makes me want to try it more as to evaluate the exact impacts.