I like how Paul Chiusano answered the main question: "If Haskell (or XYZ) is so great, why hasn’t it taken over?" "The simplest explanation is probably

I like how Paul Chiusano answered the main question: "If Haskell (or XYZ) is so great, why hasn’t it taken over?" "The simplest explanation is probably that Haskell is not that much better than, say, Java," "for many of the software systems people write today."