GSM I think that every family should have the opportunity to have one week a year all together in each others company, doing things together. It doesn't even need to be other than all together at home.
When, like some families, of which we were one, you have one of the parents whose work takes them away from home, and their children, in particular, for a large part of the year, then I consider that one week a year spent together, is more essential than a weeks schooling.
Obviously this week should be taken in holiday time if possible, but the more a parent is away, usually the more their leave time is constrained and the more likely that on occasion leave will nee to be taken in school time.
I also think many people are grossly over estimating how deleterious a weeks absence from school will be for a child of average ability or above. I went to 10 schools, highly disruptive in itself, where I went from a school, which, for example was about to teach us long division and multiplication, to one that had taught it. I quickly got the hang of it, without any extra time from the teacher.
I also lost, in total 3 terms of schooling because I spent several extended periods in hospital. Again, I just slotted back into, usually, a new school, without being given extra tution and help.
As I said, I do agree children at the lower end of the ability range may suffer, but the majority shouldn't.