My point is that whatever you want to call the governance model of Linux it isn't anything like a (non-joking) dictatorship. A real dictator could and would have stopped the Android team from leaving (i.e. made them do things his way or not at all). Linus not only didn't stop them from leaving, he couldn't.

When the benevolence is built-in, it isn't a dictatorship, it's something else. And something else doesn't support your argument about walled gardens, it undermines it.