[forkerenok]

> monads are a general computational methodology towards writing syntactically imperative-looking code in purely functional languages

I think you are conflating "monadic do-syntax" and larger concept of monad (in Haskell and elsewhere).

Many constructs in Haskell (moands/comonads/applicatives/free/cofree etc.) are just it, constructs (drawn from theory), which happen to have interesting properties. And people keep finding interesting applications for them. Some of those applications are tested with time and hence are more familiar (f.x. effect ordering with monads).