Are you seriously trying to hand wave away the risks with your weak whataboutery?
From a certain age, no, I wouldn't expect a female child to share with a male child. Do you understand that female children are getting their periods earlier and do you think that female children deserve not only protection, but privacy and dignity?
I would be finding alternatives with any school where my female child over about 7 or 8 is expected to share changing rooms? Wouldn't YOU? In fact, I DID write and complain when my child was expected to change in a facility that had no privacy and the other sex were able to see in, in Year 6. As did other concerned parents.
Would you allow your teen to go out to town if her friend group included boys?
Depends on the group, the activity and how old. Do YOU not check who your child is out with? And if there is a child present who may be an issue, seek ways to provide support to your child if the situation is something they are uncomfortable with? I quickly learned from incidents in Year 6 just how quickly and easily things can get out of hand when tweens and teens have mobile phone cameras.
Because there are plenty of secluded areas where no one would see.
No kidding. I am a parent, I KNOW this! I have also been a guiding volunteer and a volunteer with other activities... yes. I KNOW.
I also have had too many friends and family raped as tweens and teens. I am very well aware of what can and, in fact, does happen.
I am very well aware that some people will waive away risk because they don't believe it happens. It does happen. That is why there is supposed to be strong safeguarding measures in place.