Mass killings are always going to happen. The difference is that it’s a lot harder to kill a lot of people with a knife than it is with a automatic handgun or rifle. Effective range of a knife is maybe 1-2 metres. Effective range of a gun is hundreds of metres.
Still sucks that it could be mandatory. I work in a government job in Australia and we have “Flexible Hours” which means that any time worked under or over the standard 7:30hrs per day counts towards a flex balance. Then we can use the excess flex balance to then taking shorter days or even take a couple days off if we have the balance for it. It works wonders for staff morale and retention.