Earlier quoted context omitted.
Yes, things are still moving fast. AFAIK the final 1.0 version of the protocol spec was only released last Summer. The "I missed message because I only use xxx for that one thing" is valid for every app as long as you have fragmentation in the messaging space I think. That's why I like the idea of using the same client for a multitude of services through bridges, and not forcing people to necessarily use your network…
How do you deliver end-to-end encryption in a federated architecture like that?
The docs there for E2E are fairly old but get you an idea how it works. E2E has improved a lot in the last few months IMHO.