I'm honestly conflicted about generics. I see your point, and I have felt the need for them in the past. My main concern is that as of now the lacks of generics forces people to rethink a little their approach to development, while with generics I fear there will be a proliferation of not-always-great patterns that will be copypasted from equivalent Java/C# code.

The Go community has a lot of good ideas on designing interaction through interfaces that I really hope won't get lost in Go 2.

That said, yes, casting interface{} manually over and over is stupid, let's hope we can get the best of both worlds.