This is a great vision, but without trying to be a jerk, I have to wonder: isn't this just a restatement of what Erlang/OTP has been doing for at least 20 years? I haven't learned the language yet, so it's a serious question.
And if you want "Erlang validation" it's hard to beat WhatsApp's $19B acquisition. (I doubt that Facebook will be releasing any open source Erlang code any time soon!)
What does this have to do with Erlang? As far as I know, Erlang doesn't have a concept of a "stream" nor any particular mechanism for handling back-pressure.
More importantly, these kinds of developments bring the features of hipper, HN-popular languages to the multitude of enterprise Java devs who will likely never be approved to write anything in Erlang, green field project or not.
It's always a good thing when a mainstream language gets better - it positively impacts a lot more people who don't get to use niche languages for their work.
EDIT: My grammar and spelling suck first thing in the morning.
I haven't used erlang - that said, one reason might be that it's dynamically typed by default, and that the extensions for a type system have had mixed success:
"Phil Wadler and Simon Marlow worked on a type system for over a year and the results were published in [20]. The results of the project were somewhat disappointing. To start with, only a subset of the language was type-checkable, the major omission being the lack of process types and of type checking inter-process messages."
And if you want "Erlang validation" it's hard to beat WhatsApp's $19B acquisition. (I doubt that Facebook will be releasing any open source Erlang code any time soon!)
So what's the deal? If you believe in the http://www.reactivemanifesto.org/ wouldn't you be better off just biting the bullet and learning http://www.erlang.org/?