Given that the party line on generics in Go has been "Go doesn't have generics, but since generics are mainly used to implement generic collections, you can jus

Given that the party line on generics in Go has been "Go doesn't have generics, but since generics are mainly used to implement generic collections, you can just use the built-in collection types for those purposes", I wouldn't be shocked if the designers of the language only had a minimal or cursory understanding of Maybe, Either, and friends. I do not mean this as a dig or an insult, but if Rob Pike is at all familiar with the benefits of Maybe and Either (or sum types in general), then it does not show either in his work or in the talks he's given.