That's not what I meant, there's no quid pro quo in my example. My point was that neither A nor B are above or below each other in a hierarchy, and there's no permanent power imbalance between them, and yet they could both be corrupt. Corruption doesn't require a hierarchy, and a flat hierarchy doesn't prevent corruption.

Flatter hierarchy does not prevent corruption totally, probably nothing will. But it will make corruption harder and more expensive. Some hierarchies, at least context dependent, are probably inevitable. It's a matter of scale.

Yes, that would be more correct. Authority != hierarchy, but you can't have a society without authority. You could start out with anarchy, but then authoritative structures would naturally emerge anyway.