Personally I would have a system where study leave is 'earned' by your work ethic during the year. If teachers believe you deserve it and there is no particular issue with either behaviour or attainment, so, you look likely to achieve your targets for most subjects, I think you should get it.
Hmm. My dd1 had similar for her ASs. In school, dd1 was a perfect pupil, so she had study leave. She'd cruised through her GCSEs without putting much effort in, and nothing we said could convince her it would be different for A levels. Until she failed. Now, I'm erring on the side of that not being a totally bad thing at that stage - she needed to learn that. However, I don't think GCSEs is the right time to learn that. Point being, being a lovely pupil at school doesn't automatically translate as someone who will get up early, switch off all social media, and study for 6 hours of the school day, without anyone at home to enforce that.
I am a solitary learner and do well learning things on my own- reading and reflecting on what I have learnt so there is no way I would have done well having to attend study leave with others.
You can do all of that in school. Being on the premises doesn't have to equate to all sitting chatting about things in a group. Many of the teachers will sit in the room to 'be available' to anyone who needs them, and ensure there is a quiet environment for those who don't, to get on with their study.
My point is, learning in a classroom, revising with others and having a teacher instruct you, is a particularly learning style, needed by some but would be detrimental to others- hence enforcing this does not make it a level playing field!
See above. Being in school doesn't mean the staff are teaching whole class lessons. It means you are up, out of bed, and away from social media. If you want to even stick some earphones in and get on with your favoured revision method, that isn't going to be an issue for most schools / teachers. The teachers are available if needed, not forcing you to stop revising.
As Maisypops said, Walk around our y11 lessons and you'll see teachers recapping concepts, students doing mock questions, teachers doing 1-1, pairs of children quizzing each other from flashcards, teachers going through mock answers, lessons where teachers quiz students, lessons where students do silent independent study for an hour. If a teacher were doing a quiz or explaining a mock answer, and a well behaved pupil explained they were OK on that and wanted to work on something else instead, they would be able to go and work in the library, or just settle down with their earphones in, instead.