I use 'date -d' a lot when debugging our services. I have not used 'date -s' for years at least, because time is never set manually for anything even close to production. (I would have even claimed the date is set by giving no option. Not checking this now, can do when I have to set system time next time...).

This story just stresses the old rule: Never ever use root / sudo routinely for commands that don't need it because nothing can go wrong / you know what you are doing.