I'm from NL but haven't been in school for some time so maybe this has changed. So far I thought helicopter parenting was mainly a USA phenomenon. Not that it doesn't exist here at all, just not the norm, at least ten years ago
I live in slovenia, helicopter parenting is not that much of a thing, but parents coming to school to defend their kids (who did stupid stuff) sadly is becoming more common.
A friend was a cop, and same thing... kid would get drunk, vomit in the middle of the city, the cops would pick him up and take him home, and the parents (instead of thanking the cop and punishing the kid) would blame others, say that someone planted alcohol in secret (since the kid is covered in red wine vomit, that would mean planting a liter of red wine in a glass of soda), etc.
But i still think that such rules (cell phones) should be in-school rules, without the need of the governments to interfere.
It's a thing everywhere, including Netherlands. I've seen it plenty of times over the years unfortunately.
As for this specific issue, difficult parents has been mentioned a few times, e.g. in [1]: "But a smartphone ban leads to resistance from some parents who always want to be able to contact their children, including creative forms of sabotage and frustrating conflicts in the classroom".
With hundreds or even thousands of kids and parents, you only need a few to be unreasonable to cause a world of frustration and hurt.
I've seen this solved here in slovenia in (at least) one school, where they have a "classroom phone" (a dumbfone, calls only). All the parents know the number, all the kids can use it in an emergency. They are usually not used in class, but on a field trip (especially multi-day one), the kids use it to call their parents and vice-versa.
I'm from NL but haven't been in school for some time so maybe this has changed. So far I thought helicopter parenting was mainly a USA phenomenon. Not that it doesn't exist here at all, just not the norm, at least ten years ago