Attestation of identity should be seen as a service, not a product. Revocation exists. The fact that certificates are pieces of data is a compromise, not an ide

Attestation of identity should be seen as a service, not a product. Revocation exists. The fact that certificates are pieces of data is a compromise, not an ideal design. Most CAs already support OCSP, which is effectively one-day-long certificates: the client can contact the OCSP server for a signed response saying "yes, it's still unrevoked", or the server can include ("staple") such a response along with its certs. Some certs have the MustStaple extension, indicating that they should not be treated as valid unless a recent OCSP response is stapled to it. If we had the computational resources to just not have certificates at all and have every client check the CA's current belief that a public key belongs to a name at each use (and magically avoid the associated privacy problems), that would be ideal. Certificates are an approximation. One neat thing about 3-month certificates is that it's a meaningfully different human lifescale from a year (or multiple years): operators may not still be around in a year but will certainly be around in 3 months. Operators may just plan to manually renew in a few years, but generally decide they need to automate the process if it's every 3 months. (For extremely boring reasons, I manually update the certificate on my personal website every 3 months and it's a pain, and I think I am one of very few people who do manual updates to their Let's Encrypt certs.) So it forces people to think of certificates as running their end of a service with ongoing operational work, not a one-time transfer of data.