We live in an imperfect world and as a result, we need to make compromises for the dignity and safety of those who are vulnerable.
The whole reason that there has been a battle for decades for women's rights, is because women are inherently vulnerable to men, who are on average bigger and stronger.
Allowing women the privacy, dignity and safety of women-only spaces is not a lot to ask. But as soon as you allow males into that single sex environment, based on their word alone, you open the door not only for those with innocent motives, but also for predators and perverts. Since it is impossible to read someone's personal thoughts, it is impossible in law, or in a caving club policy, to distinguish the predators or perverts from anybody else, until their actions betray them, by which time it is too late for the victim.
Maintaining the right to single sex facilities is a simple protection that we owe to women, across our country and in our caving clubs.
Providing unisex facilities alongside single sex facilities ensures that trans people are not excluded, while also protecting women from potential harm.
I really don't understand why this is so controversial and has led to such vicious attacks on a club that is trying to navigate a changing world, in the best interests of all its members.