Firstly, that picture has the form he's in start to glow in order to impress someone, the fact that the chin doesn't change is telling. Nothing says that it's his 'true form' and he's obviously showing off.
Secondly, Jack Kennedy can be referred to as JFK or Mr. President and never as Jack in whatever situation, and it doesn't change who he is. Insisting that someone be referred to by name seems a bit excessive to me when it's obvious who it is meant to be.
Third, Occam's Razor: The OAA becomes Jack during his off time just to take a call and draw for a real-world old guy for no reason VS while at home he just becomes who he is when he's not explicitly trying to impress and has no reason to change his form/do anything other than relax.
Lastly, The fact that Bugs Bunny can become the animator isn't an example of how weak he is. Nor does it invalidate everything else the OAA has done if he's just a Jack with a pencil to us since we're talking about the Fiction.
Meh, this is just one of those silly threads, so I don't see why I'm taking this so seriously. Feel free to make your rules as you like, and I'll make more amusing observations in various other threads as is my custom.

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