Stopping all issuance is an pretty standard response if a CA thinks what they are issuing might be non-compliant in any way. It's an action we're required to take. It's not necessarily a sign of a more dramatic failure mode or key compromise. That said, the impact is the same for as long as the downtime lasts so it is unfortunate and we're sorry for the disruption.

I don't think the premise behind short lived (six day) certificates being viable is that CA issuance never goes down. Sure, the runway is shorter, but not that short. Most down time is a few hours or less, which is not a problem for six day certificates that should be renewed every three days.

Short lived certificates are optional though, so if it's not worth it to you there are longer lifetime options.