Sounds to me like you're describing the "achievement gap" right there. While you may be right that there isn't very much of a pay gap given equal achievement, that fact itself supports the existence of an achievement gap. After all, if women overall have lower pay, yet get equal or greater pay given equal achievement, then logically there isn't equal achievement.
Now, I don't know that I believe the axiom that given equal education/choices women aren't at a disadvantage, but at the very least according to your beliefs there exists an experience/achievement gap. That said, as a highly educated woman in a field that is traditionally male-centric, I still occasionally encounter certain assumptions about my ability (or inability) that only seem to occur in situation where the other party is aware of my gender, as opposed to online.