I agree that in your thought experiment, the program remains OO, but the language is not. You can write OO programs in many languages, but I would argue that you don't have an OO language unless it has special support for OO programming.
I wasn't arguing it was an OO language, merely that it was OO code. OO used to be done in C in exactly the same basic way, passing the struct that is the object as the first arg to all the member functions; Python does this explicitly as well.
