i don't know if decentralized is socially sustainable
I don't know if centralized is socially sustainable. It covers a small minority of human existence, during which it has caused untold amounts of subordination and immiseration of human beings, both in absolute and relative (to other/competing societies) terms. It's not even certain whether centralization as we know it will be able to exist 150 years from now.
there's a lot to be said about a clear and unified direction
You don't need one "leader" at the top to have a clear and unified direction. That is the mindset of the capitalists and monarchists.