Boy oh boy do I ever miss collection-level constructs like map and reduce in Go. I just don't think of them as 'generics' because I'm not very well-versed in statically typed languages.
I still bite the bullet and use Go anyway when it feels appropriate, because I can get fast type-checked programs with a reasonably quick prototyping cycle.
This is the reason that Go drove me to Haskell. These days I have fast type-checked programs with a more than reasonably quick prototyping cycle.
Plus after you get types down well enough, you can largely pretend you are using a dynamic language. For instance sometimes I write my functions, make sure they work right, check the type ghci says they are in the repl, and add the type annotation.
I think the amount of time I spend working on Other People's Stuff probably influenced my comment there. While I obviously use and appreciate generics for their enabling of generic operations, I tend to primarily love them for their documenting/strictness-enforcing aspects.
I thought the whole point of picking a language like Ruby was to use a language in which you can describe what you want, instead of how you want it.