Its not on the league to pay more, it’s on the public to support and put money into the WNBA. If people fill up the arenas and buy the merchandise, the salaries will increase.
I think the big problem is that the WNBA has a pathetically bad TV contract. It needs a much better, more lucrative TV deal. That is where the money is. I think the value of the NBA's TV contracts is north of $1 billion. The WNBA's contract with ESPN is $27 million--a pittance.