And I mean, girls have to be so 'guy-like' to fit into the world of fighters, I don't see how fitting into infantry units would be exponentially harder.
I would disagree. Honestly, if you knew half the female pilots and navs I do, you'd be hard-pressed to find more than one or two that aren't girly-girls. Bear in mind most pilots/navs are either Academy or university grads, so other than hitting the gym more, there's not much to differentiate them from ordinary girly-girls.
Apart from them being off-limits to some of us...

It's not as if suddenly breaking down the gender barrier is going to make all the 'girly-girls' who have issues skipping their daily shower and would miserably eat **** in the military want to join anyway.
Eh, even for enlisted folk, once the screaming and stress of Basic is over, it's back to hair, shoes, and clubs. Seriously, this place is less Offutt AFB then it is Offutt University sometimes.