The reason for backup in that case isn't so much dying hardware as it is data corruption or malicious activity. Backup needs to account for a bunch of failure

The reason for backup in that case isn't so much dying hardware as it is data corruption or malicious activity. Backup needs to account for a bunch of failure modes: data failure (corruption, malware, "Windows Ate My Data," user error), hardware failure/loss (drive death, laptop legs), building failure ("all my backups are in that safe that reached 600 degrees internally....."). Used to be that for serious emergencies you could usually get data recovered by a lab, but with SSDs that's iffy at best or likely not happening at all with drive encryption.