The main argument here is that the US women are light years better than the US men (comparatively speaking) and their games are watched more in person and on TV in the USA than their Male counterparts. On the surface, they have a great point. However, although the US men are mediocre at best, they play the world's most popular sport whereas women's pro soccer on the global scale may not be on of the Top 25 most popular sports on the planet. What this means is that the US men, by default receive a lot of money from FIFA, CONCACAF, and other federations that the US women do not. Also, if the USMNT wants to field a competitive team, they have to pay their players at a competitive rate to what the big boys pay. The problem for the women is that their sport, although popular in the USA has almost no popularity globally so the majority of their money comes from domestic "sales" while the USMNT freeloaders, in a sense off of the massive global popularity of men's International soccer.
So, while I believe we still have a long way to go close the pay gap, in general, in this country, I dont think the USWNT should be paid anywhere close to the USMNT. It's pretty simple, really. How much does the USMNT bring in (including all FIFA and overseas TV deals) and how much does the USWNT bring in? They should be paid in proportion to what revenue is brought in.