Sure. But that doesn’t mean that children should be writing rules, rather a suggestion box, or the ability to speak to ones Form Teachers and recommend that. Students can recommend things, but not force their Headteachers to act.
I’ve never seen this happen, or anything like it. Teachers are usually very understanding of situations. This is something the student should accept, and then complain about later. They shouldn’t be writing the rules.
I literally don’t care if my teachers use their phone. Emails are very important to teachers, more important than I think you will realise until you’re much older. They can have important things like landlord, electricity, or whatever, whereas with children it is easily known where they should be and do not need a phone for those situations. The students where definitely in the wrong.