Degrowth

Second thought: In history of humankind, we had all sort of sizes of societies - from small groups of 8 people up to thousands and more. It turned out in our history that humans always need someone who collects, aligns and represent a group of people - a leader. There never was any community that relied on many representatives that shared roles and reponsibilities.

That is not true, see Pirahã people for example. We have to keep in mind our historical biases, as many written records come from hierarchical societies, so egalitarian or collective models are less documented or even avoided, as that might go against their interests (E.g.: Missionaries trying to spread their religion which needs people to obey their hierarchy). We might think centralized authority seems inevitable, but it’s not the only way humans have organized themselves.