To be honest, I think it's discrimination. Not concious or malicious, but still discrimination.
The fact is that in Australia women doing the exact same job as a man (same position description), for the exact same hours, and with the same amount of experience (which removes mitigating factors like time of for kids), are paid 17% less.
Frankly, that's outrageous.
Where that's the case, I completely agree - it's discrimination (intentional or not) and there are still plenty of workplaces where it is practiced - mostly privately owned companies or organisations where "the old boys club" thinking prevails. I do think that the latter are a dying breed, and that the situation is improving where that is the cause. The former case is a little more difficult to address, but the reality is they risk missing out on some pretty significant talent as a result, and therefore also risk losing competitive advantage in their respective markets.
However I do think that sometimes people over generalise the issue and suggest that all women in all fields face more difficulty than men in getting jobs or rising through the ranks, and are also remuneratively discriminated against. I believe the reality Australia today is a little different. That is, while there are still (clearly but albeit decreasing) examples of genuine discrimination against women, this is now counter-balanced by increased opportunities for women. For example, there are special scholarships for women in professions where they are in the minority (eg. engineering, sciences etc) and awards for women only (eg. Telstra Business Woman of the year etc), yet the same cannot be said for men who want to be teachers or nurses (or other roles traditionally stereotyped for women) and I'm not aware of any publicly open awards for which men can be nominated but women can't. Likewise I'm not aware of any concerted efforts to encourage women to be waste truck drivers, brickies, combat infantry, or construction workers (that's not to say women don't already do some comparably "undesirable" tasks in other roles, like caring etc).
There are also the issues of neurological/biological differences and values, which may (or may not - I don't know) influence the data that you're referring to. For example, Men are typically "wired" differently (on average) and are more likely to be aggressive, competitive, and assertive. There are arguments about how much of this is due to "nature vs nurture" in their development, but regardless, the fact is that it influences both their drive and therefore their "success" on many dimensions.
This overlaps with values, as values influence our motivation and drive. For example, do most women think it's worth the extra dollars to be away from one's family most of the time working in dust, discomfort, danger and filth in the mines, or is the ability to devote more time to one's family more important? That's not to say people in the resources sector don't care about their families, but how many exceedingly (financially) rich people are there out there (excluding inherited wealth or employment) who can also boast that that they spend (and have always spent) the vast majority of each day with their partners and children? Some occupations allow us more opportunity for this than others, and the "same" jobs in different sectors (eg. accommodation cleaner in the mining sector vs cleaner at the local school) will also be paid differently because of other factors (i.e. being away from your family, as an example).
Does discrimination against women (or others) still happen? Yes, and unfortunately I think it always will to some extent, but I think we need to be careful that affirmative action doesn't become reverse discrimination - "an eye for an eye" style retaliation/retribution never really served to build harmonious relationships....