I wonder how much effort would be reasonable to improve the resilience of HN to this kind of issues, given that's a relatively rare issue and HN doesn't really have a money loss in case of a downtime such as this.
Probably little. There's no ad revenue being lost, no business transactions that can't be completed, no life-saving information that can't be accessed. When you boil it down, it's a social/entertainment site, nothing anyone can't live without for a day or two.
