I've never really seen this explicitly stated anywhere, so maybe this is some super idiosyncratic idea on my part, but it's always seemed to me that one of the

I've never really seen this explicitly stated anywhere, so maybe this is some super idiosyncratic idea on my part, but it's always seemed to me that one of the key pieces of OO is the use of polymorphism as a sort of syntactic/conceptual sugar around function indirection, that many people seem to have an easier time understanding and reasoning about.