Precisely, more than 10 years have passed. And Java evolved for a reason, I think. And releasing Java without generics may not have been a smart thing even back then.
But generics crosses the line because compile-time code generation is so much clearer and simpler and doesn't add any overhead to compilation times because code substitution is not compilation.
That is not a generic HashMap. See masklinn's response.
The fact is, the comparison between Go and "pre generics Java" is a bad one. There are many substantial differences, and blessed parameterized types in Go is absolutely one of them.