By using Go, it avoids a lot of existing biases. I think that's what that slide is referring to.
Indeed, the "OMG GO!1!" tone of many HN stories and comments on the language suggest that it's diving in headfirst...
If the reason is neither Python nor Ruby can do concurrency right out of the box like Go does, then sure this could be a good reason because people in Python and Ruby world would argue which set of tools to use.
I mean Python coder and Ruby coder can argue that Go is not the way to go; static compilation, like whattttttt? Strict type... like what?
I am not very convinced and think that slide is pretty biased - well basically doesn't justify why Go was picked and the tone of the slide makes me think Go is the solution to all the disputes we have in other languages. We have plenty of Go vs Python vs Ruby threads.