To me, Go is "masturbation prevention" language. Meaning that certain deliberate design choices were made to prevent precisely the types of endless unproductive masturbation you see in some other languages. I.e. type masturbation in Haskell or OOP/IoC masturbation in Java (particularly egregious, Java is not a bad language otherwise), or metaprogramming mastrurbation in C++. The omission of these features is not a bug. It's a feature in itself.
Indeed. More than once, I have seen program projects ruined by creating an overly elaborate class hierarchy, sometimes 10 layers deep. Just to express any theoretical aspect of the domain in the structure of the class hierarchy. Java programs often suffer from this. Which is especially sad, as Java has interfaces, which I think are the right way of representing abstract types for APIs for example. Interfaces don't force you to into a type inheritance just to fulfil a contract. But unfortunately, they are way to rarely used.
If anything in Java they're overused. You often see only one class implementing an interface where the programmer can reasonably expect there will never be another implementation, and where it's not exposed outside the API boundary, so the interface is gratuitous.
