I know it seems shocking but some companies do and did plan for backup systems in the event their entire windows platform blue screened. Thats why there were some companies that had a hard time with it and some that didnt.
The original poster is correct that Delta should shoulder some of the blame. The outage caused a problem but it was Deltas response that caused 500 million in damages. I’m sure that CrowdPoint didn’t advise Delta to put all their eggs in one basket did they?