I think that from the outside many rules may seem outdated and petty. I thought much the same thing until I entered the profession. And then I learned a very strangle thing. Classroom dynanics are very odd!
Left alone, a child who went to the toilet 20 times in a day would in all probability get very tired of it and stop.
If one child in a class of 30 did this, they woudl almost all want to do it! Even as young as 5. It would probably become the 'thing' to do.
And as an adult such things astonish, because it seems to be such a daft thing to do.
I teach in secondary and I can tell you that the presence or absence of a single child can utterly change the dynamics of the classroom and lesson.
Because children interact, and 'play up' to each other.
When I entered teaching I thought it awful that kids were denied access to loos in lesson time. having to have books signed to go was demaning 'outdated' and 'petty'. Then I discovered the reality; if you let some out, they will vandalise, set fire to toliets, stick soiled sanitary pads to the walls , and smear faeces over the floor! So we need to know who was in the loos when!
The 'no holding hands' (at secondary) one I also thought stupid, and outdated. Until the next school to us had a case where a girl gave her boyfreind a hand job in the back of the classroom. this is the most popular school in the area BTW and parent fight to get their kids into it.
If you spent some time in schools (and I'm not saing this as a put down or to be argumentative) you might very well change your mind. I know that spending time in a school changed mine.