I don't know.
I mean back in the 80s we had a uniform, and the girls did not wear trousers at all. If they had my dsis would have been wearing them, but it was not an option. It was skirt, blouse and tie in winter and summer dress in the summer for us at primary.
The boys played football and British Bulldog and the girls played tag, elastics, skipping games and did gymnastics. Anyone else do the "knives fork spoons.... gym movement" game? Both lots had times of climbing trees.
At secondary the boys played football and rugby and British bulldog (when it hadn't been banned) and the girls generally stood around and tried not to freeze in winter and chatted in summer. Except occasionally the boys wanted the girls to join in on British bulldog, normally far more to do with flirting than anything else. I do remember a game called "Blue Murder" briefly being popular before it was banned. I think the idea, if I remember rightly, was boy v girls tag with the idea they stripped each other if caught. Can't imagine why that one was banned!
Again the girls were in short, tie and skirt.
I don't remember any time anyone felt they were stopped because of their uniform. Yes, uniforms got ripped sometimes-that was definitely on the list of reasons when BB was banned. Parents complaints at damaged uniform. The other reason was normally broken bones...
But I don't think it's very different nowadays for the boys. As far as I can tell with ds his normal lunch time activity was football, followed by some variation of tag. Sometimes they had a couple of girls joining in; they were welcome if they wanted. When younger there were a couple who liked football. Once he'd got older the reason more often was they fancied one of the boys.
The girls do do less. They still play tag a bit; I think elastics has pretty died out round here, but I think that's just because it's not played. Skipping games and gym though isn't done. But it's not because the girls have a problem. Having talked to children fairly recently from a variety of primary schools about it, it's that they've been banned for fear of injuries. Half of them chose to wear shorts or trousers most of the time, all barring one had a polo shirt uniform rather than shirt and tie.
So is it to do with the uniform? Or is it to do with the girls' activities are not considered safe? I'm trying to think when I was at primary. There was a girl in dsis' form who three times at least broke her wrist doing a cartwheel. I cannot remember any other gym injuries at lunchtimes. I do remember football injuries and definitely injuries from British bulldog.
So maybe it's to do with our thoughts as adults more than the children themselves feeling restricted.