Yes, but there's a kernel of truth there. I wouldn't say I managed to learn Go in a day, but after perhaps six months using it I was much closer to mastering Go than to mastering other languages I'd been using for years. Go's road to proficiency is a shorter one, there's just less stuff to cover.

Take initialization for example: look at all the edge cases belabored in section 8.5 of the C++14 spec, or even the intricacies of initialization in a simpler language like Python. Now contrast this with how much lexical and conceptual space it takes to describe zero initialization in Go's spec: https://golang.org/ref/spec#The_zero_value

As in other areas, Go's approach here has downsides. (Possibly major ones.) But those tend to be conscious design decisions to minimize the total number of concepts and idioms present in the language.