Yeah. I get it. You're right. If there is only one actor, they can make decisions more easily. If there are multiple actors involved like with federated stuff, you add additional overlay by having to agree and have methods like voting, consensus etc.

My point is: It is possible. I don't disagree that takes extra work. But we live in a democraty, not a monarchy. We have technical solutions. You keep saying we need consensus between every instance of a federated software and 100% solutions. But that simply isn't true. We don't need consensus. We don't need everyone to agree. You could just expel everyone from the network that hasn't updated their server for 3 years from the network. You won't even notice the <1% users that go missing. You could implement text, audio, video, group chat mandatory encryption and minimize metadata. Make it performant and extensible and a backwards-compatible protocol. You might only be 95% of the way. But isn't that better than anything currently available? It'll probably stay that way for some time if you did it right. Just forget the last 5% to make it a theoretically perfect solution.

With the encryption: As with everything security related, it depends on your specific thread model. My example would help against everyone casually reading everyone else's mail. It won't help against a targeted attack IF you could force the fallback triggering and there wasn't such a thing like certificate pinning. But it's a thousand percent better than not doing anything at all because it could be curcumvented in an edge case. But I don't want to argue in email's favor. email is old. the only reasonable option is to start over. and force reasonable encryption this time.

Regarding the network effect: Nothing new is going to happen in the world if we don't fight it. Many people are conservative. We buy the stuff we're familiar with instead of something better. We want the things everyone has despite there being better alternatives. Americans keep using the vastly inferior imperial system. We sometimes need to get done with tasks and use that thing that is compatible with people we want to interact with. Like the messenger, the social media platform everyone uses. Microsofts office software to interact with clients... I understand. But again, there are ways around this. You could establish something nice and better in your small community and stop caring for the rest of the world. You could use something like a bridge that connects old and new technology. You can be a country and make laws that force something into existence. You can be a big corporation and just foist the the new thing on your users. Like the Instagram accounts that kickstart Threads. I don't say it's necessarily easy to do. But possible.