public infrastructure is not a key vault

public infrastructure makes copies. that is the bargain. hosts cache, peers mirror, archives retain, and operators log. after a while the original upload is only the first copy you lost track of.

that makes public systems good witnesses. publish a public key there. publish a fingerprint, a revocation statement, a signed release. those things are meant to be checked by strangers. wide distribution is their job.

private key material has the opposite requirement. it needs a small custody boundary, controlled use, and a recovery story that does not depend on an account staying alive. a ciphertext on public infrastructure does not solve that problem. it leaves an object and a trail. secrecy was never part of the service contract.

this is why hardware keys are useful. the public half can travel. the private half has a home and a custodian. the design says where each part belongs.

camouflage is not key management. a key that stays safe only while nobody notices an object has no plan for the day somebody does.

public and private key material have different jobs.