Yes, signing up on one server is much easier for people who are used to centralised services like Twitter, Facebook etc.

But as we have seen from Twitter, such a setup leaves you at the mercy of Musk-type takeovers. For-profit social networks do not like federation, they hate it as they see it as competition. It is very likely that a commercial takeover of a majority server would defederate it, to prevent people leaving and simplify its maintenance.

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