"Good evening, ladies and gentlemen, welcome aboard the 2130 ScotRail shuttle service from Glasgow Queen Street to Edinburgh Waverley. The train will call at Croy, Falkirk High and Haymarket, due to arrive in at Edinburgh Waverley at 2225. First class accommodation is located at the front and rear of the train, this is for the use of first class ticket holders only. If you wish to upgrade to first class, you can do so for £4.20. Female accommodation is located in the middle of the train, this is for the use of female ticket holders only. If you're not a woman, you can upgrade if you really want to, but this should not be done lightly, and ScotRail recommends counselling as a preliminary step."
In the unlikely event that Jeremy Corbyn's female-only rail carriages plan ever sees the light of day, I trust there will be male-only carriages by way of compensation. Otherwise, men will be much less likely than women to be able to find a seat on a busy train. That would be a form of gender-based collective punishment, and I'm not sure that's really on.