On the contrary, it is well known that ObjC and related languages represent a different strain of OO than Java or C++. In fact, people has gone so far as to say that C++/Java don't really represent "real" OO at all.

It should be obvious that ObjC belongs to the Smalltalk linage, which is quite different from C++/Java. Unless you have understood why Smalltalk is still held in high regard, you haven't understood the language.