Changing the school year gets discussed every few years, the problem is always that the exams cycle has to feed into college and university applications timetables and it's logistically very difficult to change.
Teachers contracts run from Sept 1st so we couldn't start next year before then, realistically the 2021/2022 academic year is planned already, dates of holidays published, training may be booked, teachers have to hand in notice by Easter to be available for September - it's much less flexible than other sectors. I'm not saying it could never ever change, but you'd probably have to tweak exams schedules and it would probably take a couple of years to plan because of that.
I agree that school is pretty joyless, it's far worse under covid restrictions, even when we're in person certainly at secondary kids are sitting in rows, facing the front, breaktimes are shorter or at awkward times to accommodate separate bubbles, practicals aren't happening, college placements, school trips, visits from specialists all gone. We've even put the therapy dog on zoom.
I think kids need to catch up on sports and fitness, on play and social times.
I think most kids have been working on academic study. In normal times kids miss chunks of school every now and then, catching up when everything is settled and they feel secure just happens for most kids, learning isn't a linear process it happens in bursts. There isn't a neat equation where time spent in school equals exam grade achievement.
I could write an essay on what's wrong with the current curriculum. It is dull, it's too exam focused and its ridiculous that we have high stakes testing at 16 and 18. Why?