Signal refusing to federate with WhatsApp, even though meta says they will still use the signal protocol is the most bone headed decision I have ever seen from them.
There no better chance to break the network effect than this.
Not sure what you mean, of course WhatsApp can disable it's own encryption. That would be an argument for open source third party apps and interoperability.
What I'm talking about has nothing to do with the line protocol. Each client has encryption key pairs. The public key of the first party shares it with the other parties, and vice versa. If it's encrypted with the public key then the private key can decrypt it.
If Meta gets the private keys, they can decrypt any message they want independent of whatever protocol is being used.
But aren't these key pairs generated per session and/or per contact? So once you switch to a more secure / auditable client this only matters when communicating with people on whatsapp. But they presumably have a backdoor in their app for the NSA anyway.
No body said it's going to have the same level of security, but that still doesn't mean that should just give up on it, just put a small icon indicating this is a WhatsApp user.
Every Matrix protocol server, excluding some experimental or internal for a company ones, are federating?
And it's not an app as you can choose an app, the protocol defines client<>server spec too.