That is so true, Sarah, it is for women, and very uncomfortable for men like me. That's why I never wear skirts, but only muumuus or long dresses so that I'm not forced into that uncomfortable position.
When you think about it, skirts make a great deal of sense for men. I've always thought having all those parts of yours scrunched up within a pair of trousers--or, worse, trousers plus undergarment--must be very unpleasant. Highlanders had the right idea, it seems to me.
High heels, on the other hand, make no sense for anybody. Though I'm not surprised you're finding them ever more comfortable, Susannah: supposedly when one wears them regularly, one's Achilles tendon tightens up, so walking barefoot or in flats becomes uncomfortable.