Is it your assertion that 10 and 11 year olds have brought this kind of attention upon themselves, because that’s when it starts; when most girls haven’t even completely hit puberty?
And it’s your assumption that she’s wearing that at the gym to attract male attention — and maybe she is, but women’s sexuality has been so suppressed and controlled and continues to be so that she may well have been wearing that for herself- as a way to inhabit her sexual being and try to reclaim it. Not everything is for the male gaze.
And I’m not saying that any of this is simple — but the notion that a woman has to dress modestly in order to deserve respect is a notion that has long outlived it’s shelf-life. Women don’t get respect wearing pantsuits and blouses buttoned up to the top button and they are also tired of being held responsible for men’s behavior. “What were you wearing” is still brought up in rape and assault cases.
For a more in detail explanation of what I’m talking about, read this