I am not opposed to women wanting their own space especially when there are other swimming options available. It amuses me somewhat though that Scouting, a preserve for males had to accept females, many male only golf clubs to accept women members and most gyms and swimming pools don't have men only sessions although women only sessions are prevalent. Both sexes/genders like to have time on their own just seems there's a little imbalance to me.
The scouts decided to accept girls because they were struggling to recruit enough boys to keep going, so opened up to girls.
Male only spaces like golf clubs/Masons that sort of thing excluded women very much on the basis that they weren't 'worthy' enough to join in with the big boys.
Things like women only swim sessions, gym sessions, changing areas etc stem from the fact that because of the position of males and females in our society, many women feel more comfortable changing, swimming and exercising with other women. Most men tend to not give as much of a shit because they are already in the position of power in these situations.
Maybe there is an imbalance one way, but it comes about because of the general massive imbalance the other way.