It is much harder to do functional programming in an OOP language, as one is often fighting the syntax, semantics and various defaults. For example all variable

It is much harder to do functional programming in an OOP language, as one is often fighting the syntax, semantics and various defaults. For example all variables are typically by default mutable, null in every type, libraries and frameworks with pervasive mutable state etc. Granted it has been getting easier as OOP languages have been slowly getting more and more functional features. But it really is easier to favour immutability and composition in a functional-first language.