Unless we're talking about ancient versions of C++, those productivity advantages of Objective-C are mostly a myth which I have yet to see any argumentation for.

The whole point is moot though, because Swift is the future. It's quite amusing seeing the Objective-C community trying to reconcile their irrational love of the language with the reality that Apple communicated - it's a disadvantage for the platform, keeping developers away with its unusual syntax, lack of safety and overcomplicated paradigms.