What is the point of OOP then, if you are using it in a functional way ? This just proves author's point. Do you truly use it in a functional way though, that

What is the point of OOP then, if you are using it in a functional way ? This just proves author's point. Do you truly use it in a functional way though, that would mean, that you care about separation of state and identity. If you are mostly using immutable collectons/objects with pure functions, then it's fine, but this is not OO.