I don't understand why all the ML-lovers have to bash Go for not being OCaml or Haskell or Rust. It's like bashing Python for not having static typing. Go is not one of those ML languages with a complicated type system. It has a simple type system. This is a feature for Go, just as dynamic typing is a feature for python. Neither is right or wrong or backwards. They're different design choices. If you don't like it, that's fine, don't use it. But it's not an inherently bad choice.