You’ve misidentified how a decentralized, federated network of content sharing works. Like many, many people, you seem to have conceptualized it as a hub-and-spoke model, with a centralized data store and remote terminals.

But it’s actually a subscription-based mesh network, where each update is only sent to places that have specifically requested it. Importantly, at the moment at least, things are not forwarded along to other servers due to secondary contact. If someone on my site (A) subscribes to you (B), and someone on a third website © comments on something you posted, if nobody on my website subscribes to C, C does not send that comment to my website, and your website does not forward it along, either.

There’s some buzz about forwarding replies and stuff like that possibly getting worked out. But even then, being on the fediverse means making peace with the idea that there’s no single source of truth for the whole network. You won’t see it all, ever. And it’s likely, and possibly even desirable, that the network splinters into loosely connected islands. But that can’t happen if what people keep demanding is a centralized service with a single benevolent dictator. And the single dictator will stop being benevolent at some point.

They always do.