Wow, first I've heard of the Dallas/USWNT match. Surprised this didn't gather top sports coverage in the US - it surely would have if the Men's side lost to a U-15 girl's side. The "world champions" losing to an U-15 boys side. Guess that should put to rest the lark that the Women's team could beat the Men's team.
Because it's not a particularly big deal. I live in Dallas and this got a little bit of attention locally from sports radio shows, but then people actually knowledgeable about how the USWNT practices explained that they regularly scrimmage men's sides (youth and adult) because it's better preparation...and they frequently lose. I'm not sure anyone other than idiots really believed the bolded statement.
Money.
Manchester City have invested heavily in the women's side of their game - poaching the best players and paying the highest wages. And to their credit, they've put equality at the heart of their new training facilities.
However, it's loss-making. They're not gaining anything financially from having a team in the Women's Super League. It's effectively a loss-leader - promoting a product at a loss, but knowing that it'll attract investment, support etc into the brand/club as a whole. The club don't have the interests of female footballers at the heart of their ambition, but rather the good PR and brand exposure that results from it. But in truth, said exposure is a fraction of what can be achieved from other initiatives.
Without wanting to sound sexist, there is a ceiling to the women's game, and it isn't that high. United acknowledged this long ago and chose to pursue other avenues.
How do you profit from something that is boring? That's the crux of the issue. Women's football, to the masses, isn't entertaining.
At this moment in time, there is no incentive to United investing in a women's game. And I doubt there ever will be.
Right now, any owner investing in women's sports goes in knowing that, except in rare instances, it's a financial loss in the short/medium/long run. That applies to football in England, the NWSL in the US, the WNBA, Women's College Basketball, etc. etc. You do it because it's most likely the right thing to do and because you're trying to create the groundwork for future generations of women both from an athletic standpoint and a marketing standpoint. Youth participation stats show that participation rates for girls in women's football continues to increase in England and the US. Even though, developmentally, professional women's football is very much still in it's nascency it's important to get in at this ground level.
As far as the part that's bolded, you're not appealing to the masses right now. Women's football isn't developed enough to be appealing beyond a small base of viewers, and most of the people on this forum certainly aren't the target demographic.
Being as far behind City as we are in areas like this, or our website from the 1990's, or our social media presence which resembles that of an insurance company isn't a big deal right now or in the near future. It's just a combination of things that make us less accessible and, honestly, less attractive to younger generations inside and outside of England, which could potentially hurt us down the road.