People were pretty excited back in the day. We may look back on this excitement and think it's unrealistic, and indeed it is. That is the Hype Cycle at work. People can't get enough of the shiny new thing, and will inflate things to make it look even better than it is. You have to watch out for the effect, as it's very common. The inflated expectations is what causes the transition to the Trough of Disillusionment as people begin to realize that what they were promised is an impossibility. In the case of Go, the lack of generics was a good sticking point. Here an article has promised me that Java is dead. But Java has generics. I guess I was lied to! The result was many breathless battles over whether or not generics were really necessary.
Again, you have to understand that HN's biases play into this effect. There are many people here that want to be at the forefront of the field, but are outraged when they have to show up at an interview and code up a data structure on the whiteboard. If generics were in Go, then someone else would have already written the data structures, and they could continue to believe that the practicing programmer has no need to ever look at a computer science textbook. But the reality is, when you use Go, sometimes you have to show up and write an algorithm or a data structure. (The most common one I've written is an ordered set; a slice with the keys, and the keys and values in a map.) So you can see why emotions are going to run high. Two ideals are in direct conflict -- and generics are going to solve the emotional problems. Thus, much is said and argued on these topics.
I have to say, I sleep way better at night knowing that the Go team is around to deal with all this stuff. There is a lot of arguing and strong emotions, and they sort through it all and continually produce something that seems sane. Because they do such a good job, I don't have to feed the hype cycle, I can sit here and enjoy the view from the Plateau of Productivity.