Earlier quoted context omitted.
Yes, they should be unhappy about that: at their managers. Not at their colleagues attempting to care for children during a pandemic. I've heard a related thing about US workers resenting colleagues for taking paid time off for similar reasons, and it's just as weird to my European eyes. The difference a decent labour movement (or the legacy of one) can make to industrial relations is stark
Any manager that’s laying out timelines assuming that everyone will work at 100% capacity permanently is being unbelievably naive. People will take vacations, get sick, or need mental breaks. We’re humans, not robots. If a team can’t handle someone losing velocity due to the challenges of parenting during a once in a century pandemic, then it needs new leadership, period.
The second part of comment is asinine trolling. No one is ready for once-in-a-century thing by definition. If once in a century flood leaves the team stranded and water still does not drain away after 6 months it has nothing to do with management. There are no continuity plans for disasters that keep happening for such a long time.