They're easier to pick up and support the idea of plug and play programmers that is very popular among managers.
Productive as a consequence of the above, maybe; in that more code is written in Go; but certainly not as a quality of the language.
And there's numbness and denial involved. I've been writing Go full time for about a year now at work. Every time I use another language I'm reminded of how much time and energy I'm wasting.