Exactly. And no civilization on earth has yet solved the "Power tends to corrupt; absolute power corrupts absolutely." problem at scale. In what society does power not exist in some form? In even the most primitive of human societies the first and best portion of the meal would be given to those who had the most political favor. We have control of a single vector in this equation, the size of the government. I see no other way.

You're not looking very hard. As I suggested above, we can pursue government policies (largely independent of government size) that favor decentralization. We don't have to throw up our hands in defeatism. We have perfectly good processes to implement these policies and improve our society. The only real obstacle, frankly, is the kind of fatalistic passivity you're proposing.