I always like videos that remind people to have reasonable backup and maintenance schedules.
Seems like they intentionally caused this for additional YouTube content?
That's why you use managed solutions.
TL;DW?
Put 780 TB of data in one big cobbled-together server, didn't have backups, too many of the disks died/got corrupted before they noticed because they never ran integrity checks on the file system.
Two servers actually. they have damage to both servers, as I read it, due to never scrubbing the disks, and having physical hardware failures and poor power quality.