![](https://feddit.de/pictrs/image/4ffd6476-60ed-4432-a40f-d716c2948bec.png)
![](https://lemmy.world/pictrs/image/eb9cfeb5-4eb5-4b1b-a75c-8d9e04c3f856.png)
What I mean is that a subset of all Linux communities agrees on a common set of rules and forms a community of communities. Content of all communities is shared with everyone who subscribes to one of the communities. Every community moderates its own content. If one community decides to have stricter rules than the others it can defederate. Basically just like on the level of instances.
What stops us to just defederate from lemmy.ml is that the community is hosted there and all members are linked to that one point of failure.
No. Mastodon and twitter are short message services. Lemmy and reddit are content aggregators.
Instance A also cannot moderate the content of Instance B. Your argument is therefore invalid. The point of federation is that instances can agree on a common set of rules and values or not. In that case they defederate from each other. However, this doesn’t work in practice as communities are centralized. Obviously, most of us agree that lemmy.ml is a problem but we don’t federate just because they ‘own’ the instance.