I think the flak came because Go didn’t incorporate functional language features or generics which are deemed “kool” these days. Go is designed to be predictable, efficient, readable and maintainable. Anyone who has to maintain Scala code will know the pain. Look at Java generics, it’s a mess and you have to bend your brain to understand it, except for simple cases. A language that makes no effort to make its codebase readable and maintainable will incurred high TCO(Total Cost of Ownership) and subsequent abandonment.
Despite lacking all the “sharp tools”, Go code is easy to read and maintain.