Oh yeah, I don't think it's a perfect fit either at the moment, and for the vast majority of women, it isn't. But the reasons that hold validity aren't really the 'but what if blokes start covering the girls and not the boys?' arguments IMO, rather, cultural factors within the Army and the difference in physical makeup between men and women causing problems. Who knows, maybe they might find women being better suited to being section medics because of their higher extroversion on average or something?
From memory, current policy dictates that on exercises, women are required to have access to shower facilities and all the rest of it every 72 hours (menstrual cycle being the primary reason, I believe), whereas the blokes are still expected to go weeks without a nice hot one. Obviously, this is going to have to go if women are integrated into Infantry units, but this, as well as things like the difference in fitness standards between genders are some of the larger reasons the culture isn't so conducive to women being in these roles, IMO. They don't exactly foster equality between the genders when there's some groundwork to be done on that front. The first step to attaining actual gender equality within the defence force is to actually make things gender equal, although I believe something like close to half the women in the ADF would fail the basic fitness assessment if they had to perform the male assessment.