Children have been led into toilet cubicles and harmed. This happened on a big scale in Rochdale but that was men and boys. However I know of incidences in schools, then stations, supermarkets, shopping centres, railway carriages. Lots of busy public places.
I can’t imagine anyone going into a set of toilets and not intervening if they thought a child was in trouble. However, if you have a mixed sex cubicle they are designed to be resistant to sound and not have door gaps. Basically any private space in a public area has not got any supervision inside the cubicle and is more likely to have things going on in it that are illegal. There is a specific clause in the sexual offences act 2003 making it illegal to have sex in a public toilet but that doesn’t stop people if they think are likely to get away with it.
If we had single sex designs with door gaps I think there would be less sexual assaults in toilets. You would be able to see how many were in the cubicle and hear sounds.
Obviously there are exceptions when the only option is a mixed sex toilet room. But we shouldn’t be advocating for more of them. CCTV is retrospective.
I agree with you that the mixed sex toilets need to be appropriately designed. This means in an area where who is going in and out could be closely monitored by a human, and checking if people were ok if they were in for too long. But we may end up as a country carving up single sex provision or creating unisex toilets in completely inappropriate, isolated places.
I would say though that single sex provision is isolated and enclosed and is directly off a mixed sex space, it is not much better. It’s just unisex with a different pictogram on the door.
I know from my research, it’s the design that’s the factor as to whether it’s safe. Mixed sex are never as safe.
Going back to the original OP, I think there are many tiny cameras inside mixed sex toilet cubicles/rooms (privacy gives the time and accessibility to set them up) so voyeurism is less risk and more reward.