Earlier quoted context omitted.
Go's designers have very different goals from others. They did not set out to design a language they would, themselves, like to program in. They meant to make a language that very distracted programmers would still be able to get things done using, and other distracted programmers could read and maintain. Java also was not a language its designers wanted to use. They would rather code Lisp.
Still no excuse no to learn from the mistakes of others, Go has already so much "we don't do that here,...., ok we really should support that" that will eventually be just yet another Java, but hey it has cool designers.
You have to be arrogant to design a language and expect it to go anywhere, so you also tend to think you know better than everybody else, and that nobody has anything to teach you. It's an occupational hazard. Designing a language you don't mean to use yourself manufactures special failings.
Rust's designers started with unusual humility, and have kept it. It saved them from many mistakes.