I'm curious why you say fortunately? I find it to be quite a down side that type parameters are missing. In fact it's quite confusing, because there is nothing that indicates a constrained interface can't be used in place of a regular one (until you try it). Personally, I think they should be included simply because they are a side effect of the generics syntax and it's much more confusing without. Also, they increase clarity and type safety, which are two of Go's main advantages.

Also, type parameters were supposed to be included, but were dropped because it made the implementation more complex.