> Objects can have a private state. This is a problem with mutability, not oriented object programing. You can have non mutable OOP.

Wouldn't this violate the "encapsulation" pillar of OOP? As far as I know, it's always taught with encapsulation, inheritance, polymorphism being its three pillars.

> How has OOP created a software industry that would not have existed if functional programing had "won the fight"?

I'm not sure functional programming has lost yet. I haven't worked with it personally, and so can't speak to its merits or demerits, but have heard a lot of buzz around it recently. As you said, people tend to hype everything; some stay and some go. It might be the next big thing in programming, or it might be hipster tech. Or, like most things, it might have some good applications, but not be applicable to everything. That's basically my argument for OOP.