Which nullifies the point of certificates having an expiration date (limited window for exploiting a compromised certificate, possibility of domains changing hands), not the point of validating the signature (tie responsibility for apps to who owned a domain on a specific date, allow third parties to create blacklists of bad developers).
How? Expiration doesn’t grant an unauthorized party access to the private key.
There’s zero cryptographic reason to have a signed date at that point.
Which nullifies the point of certificates having an expiration date (limited window for exploiting a compromised certificate, possibility of domains changing hands), not the point of validating the signature (tie responsibility for apps to who owned a domain on a specific date, allow third parties to create blacklists of bad developers).