This line of reasoning never made sense to me because there's plenty of stuff in the language that isn't absolutely needed, such as the various special syntax for certain concurrency constructs.
They look at how their software is being used and the problems people are encountering using it and then decide what is the best path. To roughly quote Rob Pike 'every feature is useful, but they all have a cost, and its about weighing the outcomes'
Its actually not designed to meet Googles requirements, that just something people who don't know Go say. They have a survey they put out every year and take feedback from customers on issues that arise. They try and fix those issues with as little code as possible, because code and features have a cost.
Caught me, Go was developed for Google only because it fits between C++ and Java meaning its worthless to everyone else ;)
Generics and dep management were on the top of that survey last year. They are the primary focus of the Go team right now. Russ wrote Go Modules for dep managment, the implementation specifically addresses pain points from the community. Generics are a hot topic and looks like we're close to a finalized design.