[Dewie]

The problem with advanced type systems is that, while the theory and implementations and the research might be mature, it will take god-knows how many years of research oriented on usability in order to get something approachable and understandable. If people are even researching usability like that in a systematic manner (I have my doubts whether there are PL researchers that are working on that kind of thing, or if the community has just thrown their hands up and said that it isn't doable).