Jcvi can’t comment on every individual case; only in general. Each child will have a unique situation and so if the risk/benefit is marginal, why not let people decide?
Child A has no previous medical problems, walks to school, has no close contact with Vulnerable people. Had covid before summer and no significant effects. School has great home learning program for those isolating and child has good internet access.
Child B has mild asthma, sibling had glandular fever 3 years ago - which took them a long time to recover from. Parents have some medical problems but not classed as CEV (though vaccinated). Commutes via public transport. Poor internet access. Lost lots of school time during previous lockdowns due to bubbles sent home but never tested positive. school did not have good home learning program.
Just examples of why people in different situations may want different things. I hope people can be supported to talk to medical professionals if they are worried - like pregnant women are.