There is an old story from the Computing Center at the University of Copenhagen, around 1970 (so, no URL reference to the event ).
BryanFazekas wrote:I doubt that this situation is exactly by design, as the accounts affected are not ones that have been dormant for 2+ years
Clocks with battery backup were not common. After a power failure, the operator had to type in the current date and time of day on the system console. It happened that the operator mistyped the year without discovering that he missed by a decade. Before the mistake was discovered, they had run the cleanup program that deleted all files that hadn't been touched for six months.
There is an interesting 'Part 2' to this story: Disk space was terribly expensive in those days, so all large data sets were kept on 1/2" magnetic tape. The cleanup program didn't wipe the tapes. But ... Standard tape formats, used when exchanging data with other installations, contained complete metadata for every file. Even tape was expensive, so Univac (this happed on a Univac 1100 system) had devised a format where only the data blocks were densely packed on the tape, while all metadata was maintained on disk, for fast searching for files. All this metadata was wiped by the cleanup procedure. The 'real data' was still there on tape, but on which tape? Where on that tape? Noone could tell.
Our professor, when telling this story, said that a for a few very important projects, the viable tape wheel candidates had been dissected by hand, and the blocks put together, like a giant jigsaw puzzle. Fortunately, in those days, a lot of research didn't depend completely on the computer, it was more like a calculator that you picked up for specific calculations; that was all.
Imagine the situation today, if the next pandemic doesn't infect humans, but the virus thrive on silicon and is capable of getting through the shields to eat every logical gate of all digital electronics on earth. I have difficulties finding a single (Western) human activity that could continue completely unaffected if that happened.