It disheartens me a bit when people compare Go with C++. It gave me the impression that Go was created to be better C++ (or Java) mostly to make life easier for the thousands of developers at Google who are stuck with those two languages.
As with most programming languages, there is a small Scala following internally, but it's not a production language.
I don't know anything about any discussions about Scala. If I was thinking of deploying Scala, I'd be worried that Scala just doesn't offer enough over Java to warrant writing in a new language. Writing in Scala means not that you have to know it, but everyone who inherits it, and everyone who has to interoperate with it. The overhead is just too great to make a good case for writing something in Scala.
Go has almost no cognitive load beyond the complexity of the algorithm itself.