In contrast to the other comments, this is actually one I 100% agree with... and is part of the downfall of federated systems (which I have given short talks on

In contrast to the other comments, this is actually one I 100% agree with... and is part of the downfall of federated systems (which I have given short talks on before <- not to advocate for centralized ones, like Moxie does, but to advocate for fully distributed ones): they tend to end up with a small number of heavy instances designed to provide better moderation, security, or discovery with the result that you end up with little fiefdoms with peering agreements instead of a system where anyone can actually talk to anyone else. And yet, the status quo with email is nowhere near as bad as it is sounding like with Mastadon.