Structurally, Mastodon gives too much power and responsibilities to instance administrators. Instead of putting them in a position of power, Mastodon should give more power to users by allowing them to organize the way they want and enforce their own moderation rules. For me, a Mastodon instance should be a computing resource (a server) meant to host user contents and no more.
Mastodon instance should put power on users, not on the administrators. Mastodon should make people able to create public and/or private groups in which they are free to enforce their own social rules (moderation, visibility...). Mastodon instances should be tools like hammers, not services. A software should not enforce social rules by default because social life is not data driven.
A software like Mastodon should give people power; the power to organize by themselves, power to be themselves. I dream of a social network where I can visit a friend and then go to a party without having to take public transportation. Social networks have to break real life gates, should invent another way to be social, should put power on each individual.
So Mastodon and the like are federated systems. It sounds like what you want is peer to peer. I do too :-)
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