Of these, I would consider only Java to be a true OO language.
Python: Sure, everything is an object, but you don't need to know much about OO to use them. I program in Python professionally, and rarely do I write classes (unless I'm using a framework like Django that requires them). Also, if your language doesn't support data encapsulation, can you even call it OO?
JS: Wasn't OO a later addition to the language? You can get a huge amount done in JS without classes, and that isn't considered poor JS. The general push in JS is to go more functional, not more OO.
C++ is just C with an overly complex OO appended to it. Again, you can write fantastic code in it without relying on OO directly.
JS is a prototypal language, classes are just sugar on top of the prototypes. It's still a flavor of OOP (Self, the original prototypal language, was basically Smalltalk without classes). Ruby makes heavy use of OOP, but allows procedural style of programming similar to Python. You look at Python data science libraries built on top of Numpy such as Pandas, and you see plenty of class stuff.
The web DOM is object oriented. But sure, in these languages you don't have to write your own classes and methods, use inheritance, etc. But plenty of code has used it, and somebody is maintaining, using or extending that code.
The point isn't that OOP is inherently bad and should never be used, but that writing OOP code well (as opposed to merely using objects) is nontrivial. Hence the "seeing how most adult programmers do OO poorly" comment. We've had lots of problems with universities starting off with OOP in the introductory course. I would not deem it suitable for kids unless they are already good at procedural programming.
Of course good stuff has been written in OOP. I personally like that Django uses OOP - it's a good fit. Doing it well is not easy, though. And many problems are easier solved without it.
> JS is a prototypal language, classes are just sugar on top of the prototypes.
Is OOP now a vague term, akin to "functional programming"?
I still maintain that not having data encapsulation (i.e. Python) means it's not OO. (Not that I particularly want it to, either).
Python: Sure, everything is an object, but you don't need to know much about OO to use them. I program in Python professionally, and rarely do I write classes (unless I'm using a framework like Django that requires them). Also, if your language doesn't support data encapsulation, can you even call it OO?
JS: Wasn't OO a later addition to the language? You can get a huge amount done in JS without classes, and that isn't considered poor JS. The general push in JS is to go more functional, not more OO.
C++ is just C with an overly complex OO appended to it. Again, you can write fantastic code in it without relying on OO directly.