I’m ready to defer to your expertise (or any expertise, really), but aren’t we just disagreeing over terminology? By a “federated system” I mean that there is

I’m ready to defer to your expertise (or any expertise, really), but aren’t we just disagreeing over terminology? By a “federated system” I mean that there is a relatively small number of independently operated first-class entities (servers, nodes) that are more permanently connected and host a large number of second-class entities (users, points) that are more intermittently connected and generally correspond to individuals. Internet mail, IRC, Jabber and Matrix are federated; Slack (centralized) and BitTorrent with DHT (peer-to-peer) are not. The Internet itself is complex enough that it probably doesn’t usefully fit into this classification. In this sense Usenet and FidoNet are both federated store-and-forward mail systems. Or am I wrong?