A modern programming language that makes developers happier.

kotlinlang

I think its because so many programmers and projects are thinking its only the theoretical performance of their software that is important, but actually its the actual performance of the software developers, low cognitive load, no spooky action at distance, and fast feedback time. 
A lot of people don't believe that fast feedback means under 1 second, entirely achievable with software like http4k.
Async and friends give performance benefits in a very limited set of use cases, most software projects don't have constraints that make the additional complexity of writing, and the additional complexity of debugging worthwhile.