I was rather annoyed to hear that, even on the hottest days this year, pupils at my DGD's school had to keep their blazers and ties on at all times. I doubt that the headmaster was wearing a jacket and tie.
It really is rather ridiculous.
The idea of school uniform is not a bad one, imo, because it eliminates the stress of dealing with a child or children in the morning who are insisting on wearing unsuitable clothes for school and also eliminates some of the competition of wearing designer clothes, designer trainers etc.
However, the expense of school uniform has got out of hand and if the law changes that schools cannot insist on only certain suppliers being used then that is a good thing. Lots of outlets sell perfectly good school clothes.