They seem to depend on hierarchies but there are decision making processes that do not depend on hierarchies even tho they might resemble them on first glance. You can have a council that makes decisions on a consensual basis, sends revocable delegates to upper level councils. This might seem like representatives as in modern parliaments but the revocable part is important. If they can be called back at any point and the position is temporal from the start, this changes everything. Also decisions should be on the lowest possible level and everything must be voluntary.
They seem to depend on hierarchies but there are decision making processes that do not depend on hierarchies even tho they might resemble them on first glance. You can have a council that makes decisions on a consensual basis, sends revocable delegates to upper level councils. This might seem like representatives as in modern parliaments but the revocable part is important. If they can be called back at any point and the position is temporal from the start, this changes everything. Also decisions should be on the lowest possible level and everything must be voluntary.
Just confirming, this is a hierarchy. Certainly in your comment a better designed hierarchy, but still a hierarchy