Reading bits and pieces of the full study (I was looking into the hormone therapy issue), seems like it comes down to numbers.
While the number is poorly defined, there's just too few transgender people to make a dent, especially after you split them up into categories. Seriously, the transgender population can fits within the error bars for the normal population.
As for hormone therapy precluding service in certain places, that's what Britain does. Seems straight forward considering the numbers.
And if you guys are going to bring up education and shit. Bring up Viagra, condoms and birth control. I'm quite sure service members get those. Ideally they don't fuck around but the military isn't going to stop it from happening.