Most CAs already operate an OCSP responder which supports querying daily (if not more frequently) to make sure a certificate still hasn't expired; it checks the

Most CAs already operate an OCSP responder which supports querying daily (if not more frequently) to make sure a certificate still hasn't expired; it checks the database and responds with a signed and timestamped acknowledgement. (Those that don't need to support frequent queries of a static certificate revocation list file.) So this is already a level of requests that CAs have to be built for. And even if it didn't, scaling certificates from once a year to once a week requires merely 50x capacity - a finite number, and something that's very easy to plan out. If CAs in the '90s and '00s were able to handle a certain once-a-year request load, surely CAs today can handle 50x that.