[quatrevingts]

He states that H-M is not used because of the lack of reified generics, which is completely irrelevant. (Hint: type systems perform analysis at compile time; "reified generics" means having type arguments available at run-time.) H-M is not used because it is not compatible with subtyping or method overloading, which are both critical for Java interop. There is no particular reason that Scala needs to use exactly the H-M system.