We've all been using one since the 80s: email. The interface is just poorly designed for social networking.

The email we've all been using is not all open-source and end-to-end encrypted, though there are open-source clients, some of which support end-to-end encryption.

em... the only thing that is valid to support end-to-end encryption is the end client. Otherwise it's not end-to-end.

Yes, and the end clients many people have been using don't support end-to-end encryption. So, we haven't all been using a e2e encrypted system already. We've been using a system over which e2e can be layered, and very few have been layering that over it. And many using it in a way where even with an e2e protocol, it wouldn't be secure, since they are using an third-party, remotely provided client that can be changed without their notice (webmail).

Well um, if you have an open protocol then instead of a monoculture you have many different clients, and you can't expectto CONTROL all of them and what they do. That's the whole point you are making in the first place. The irony is if you have true freedom and openness on all levels then you also can't control the tools that don't maximize their users' freedom/security/whatever so users of those tools are still locked in.

But YOU can choose to use what you want. And IT can choose to require certain things of those it communicates with. And now you're right back to less freedom in the name of more freedom, hehe.