Having done a lot of research on this, I can say there's still a lot of mystification around it. Unfortunately, a lot of people still parrot the 77 cents thing, despite it having no specificity. On the other hand, there are still many problems. The adjusted wage gap is still almost 10% (at its highest,) which is disturbing, since most of the recent studies, like the CONSAD one, control for almost every variable we can currently manage with our data- with all those controlled, there's no reason for a woman in virtually the same position with the same background as a man to be making that much less money for the same amount of work. More has to be done to see why that still exists. Beyond that, more ignorant folks tend not to focus on social factors that mediate people's choices to enter various careers, and also things like glass ceilings, which are not accurately measured (or measurable) in these studies about the adjusted wage gap. The "liberal" (conservative, libertarian) argument that there couldn't possibly be any social factors that lead to demographic trends in career choice (beyond men being generally physically stronger, or other biological factors) or that those factors shouldn't matter in social analysis is weak as hell. It's the same logic that attempts to cover up racial discrimination by pretending there are no institutional factors that influence, constrain, or enable choices.