> Generics are genuinely tricky: They allow you to write many kinds of useful functions in a type-safe manner, but every known approach for implementing them adds complexity to the language. C#, Java and Rust all bit the bullet and accepted (some) of this complexity. Maybe Go will find a sweet spot, preserving its simplicity but adding a bit of expressiveness?

I seriously doubt Go and the people who maintain it are going to do groundbreaking work in this area. It's and extremely developed area of language design (and still developing way ahead of where Go would ever go)

What "complexity" does simple parametric polymorphism (i.e. forall a) bring? The only thing I can think of is some extra syntax, which is far less complex than a codebase built upon a lack of parametricity. Hell, don't even allow user-defined parametric types and force everyone to stay with Go's parametric builtins but allow programmers to abstract over them. Seems like a no-brainer to me.