The thing that this 1997 is missing is the retain - release mechanism, found "only" in classes, that are derived from in NSObject, and still a key Obj-C feature

The thing that this 1997 is missing is the retain - release mechanism, found "only" in classes, that are derived from in NSObject, and still a key Obj-C feature. I don't really know when exactly was this added to NeXT/Cocoa API, but I think it's important to note.