The fact that the product seems to have no concept of holidays when its essentially a scheduler++ is a problem.
The problem with doing trades which is the default easiest thing to do given the PagerDuty interface is that when you come back from (or just before you go on) vacation you typically end up with extra bonus on-call shift outside the cycle. Delightful!
All these things just sort of pile up into the "maybe its just easier not to take a couple days off" category, which is not really a mistake on your employers part.
Depends on the service and industry. Banking adjacent companies are often allowed downtime off US business hours. Even at big tech companies I've run internal services that had business hours support only (nonproduction sandboxes, non-business-impacting services, long running job services with SLOs measured in hours or days)
Honestly as a consumer this pisses me off. I get home for the day, relax, eat dinner, and log into the bank to check my finances at 8pm and east coast banks throw up a "scheduled downtime for upgrades" notice.
Do you shut down your service for Labor Day? I don't.
I do agree that trading on-call shifts is not very easy within the UI. Part of me dreams of being able to make enough advantaged trades to end up never on-call, like the padre who doubled his holdings in a WW2 POW camp: https://www.ft.com/content/c523efe6-9973-11e1-9a57-00144feab...