In my opinion, the FP/IP split is fueled in no small part by a wildly divergent set of vocabularies. A dozen different <greek letter> transforms are inscrutable to anyone who has not spent much time studying Lambda calculus, and the concept of a monad is famously difficult to explain.

You wind up with two camps that cannot communicate. It's often made worse by the functional programmers - who are mostly also imperative programmers - doing a poor job of enabling translation.