Basically every kindergarten, primary school and high school will want to post pictures.
Here (NL) we get a form at the beginning of each school year to mark which uses of photos we find acceptable. E.g. we allow photos in the school portal (which is private and not owned by big tech), but not on Facebook, etc. It's the way it should be done, because there is not much burden on the parents. If the school also wants to put photos on social media, the burden should be on them to make sure that kids for which they don' have an ack are not put there.
A bit harder was initially convincing my parents not to put pictures of their granddaughter on Facebook. They are understandably proud and want to show their friends. But they respect it.
I think in all her life there has only been two violations of our policy. In both cases we contacted the person who published the photo/video and they took it offline.
You just need enough 'weirdos' to make it normal. I know that there are other parents that agree, but not everyone has the gut to stand up to the social media tyranny, but will join if some people set an example.
I do wonder also if the blur effect they use is one of those that can easily be reversed. I need to check that one of these days.
Honestly what's the point at this point? Are parents not going to send their children to that school because they didn't see pictures of blurry-faced children having fun on the Internet, or is this just teachers wanting to post about their students?
LinkedIn was used in a similar manor, to coordinate meetups for our local Cloud Native meetups, but the LinkedIn algorithms are much much worse than Facebooks, so people would get "You might be interested in this meetup" two weeks after the event.
Facebook basically took over communication, no more mailing lists, no more updates on the website, if there even is a website. You just have to accept Facebook if you want to be notified about changes in scheduling, upcoming events or general information about your kids soccer practise.