Parents can't take it as read that removing their child will have little or no impact
Well they can, because they know their own children, and they can assess whether it will harm them or not. I know that a week off school will not harm my children, and I know when to plan it for the best time, and I know how to help them if they need to catch up on anything they missed.
or that school can manage this impact for them
I don't expect the school to manage it at all. I imagine some do, but just tell them it's up to them. I find it a little irritating that the implication is that I don't know enough or am not able to manage this for my own children.
Sometimes it will be harmful, sometimes they will be fine - not my circus, not my monkeys
No, they are my monkeys, and if I want to take them to the circus, I will. I support and value the school, I love my kids teachers, they are great. And they have no problem with my holiday plans.
I'm not being arsey when I say I can't understand why its such a problem in the UK, but then we don't seem to have half the problems that teachers in the UK have, we don't have a retention crisis, they don't work nearly as many hours or seem so stressed. All the teachers I know are very happy people, on the whole who enjoy their jobs.