It's an interesting debate, so thanks for starting it.
I think Dan feels that a decentralized project or app shouldn't have a strong leader who's ideas will be followed blindly regardless of their quality. And I'm guessing he feels leadership wouldn't truly spread to the community if he stayed around.
But to follow your train of thought, it could also be said that he just keeps developing his Graphene project and hasn't abandoned it yet, what do you think about that?