Just think of IPL, at the first season. It takes time and it is a wrong calculation to compare men's IPL with WPL in terms of revenue. Even before the start of WPL there is not much interested on it. Now the audience and viewership have increased than calculated. When the franchise number increases automatically it'll gain even more popularity. Maybe WPL isn't that profitable as IPL, but it is sure to generate profit, no doubt in it.
Men's and women's league will never be equal. It doesn't matter how big an investment or promotion, it will never get the equal position. But its good and bad things can be judged comparatively. The Womens Premier League has just started. If it will not be 100% successful this year but there will be more improvement in the next seasons. If a few sessions can be completed regularly then a big revenue can be earned from this tournament. At that point we can make a comparison of the women's league with the men's.
I agree with @Vaskiy that comparing women's sports with men's sports is not fair. But at the same time, we all have to remember that this is not a charity. Unless they bring in good revenue for the investors and sponsors, they are not going to be interested in investing. Of course, it is going to need time. But is the BCCI going to give women IPL the time it needs? Considering the fact that they did not want the women's IPL in the first place. I don't know their situation now but that was the case for a long time.
It was truly said by @BobK71. Comparing men's sports with women's sports is like comparing world-class cars with Nissan. You are going to get your money's worth with a Lamborghini. People will also show a lot of interest in a Lamborghini. With a Nissan, you might get reliability, but you will certainly not get the popularity.