Women's hips sit higher than men's, which makes their leg/height ratio higher.
Basically, on average a shorter woman would be able to reach the pedals, hence the lowered "sitting height."
OK. Without devolving into the "what is 0 G" type disussion, butt-to-knee length and butt-to-top-of-head distance are irrespective of where your hips are.
Let's say that person A is 50%legs and 50% torso/head. If that persons legs reach the pedals and its head fits under the canopy, it fits.
If person B is 90% legs and 10% head/torso, and all of the same criteria are met, then they fit too. Granted, this would be a weird looking person, but they measure all of your different parts individually. It's not just about height.
Anything that you "saved" in butt-to-knee length because of leg/torso ratio you would "lose" in sitting height. Either way, it doesn't matter if you are male of female.
I think that whoever said that it was about recruiting numbers and opening up the size of the female applicant pool makes more sense.