There’s a big problem having a woman as your action lead (other than it’s completely asinine, as women lack the warrior instinct as well as the physical strength): you can’t have the villain beat them up.
In ESB, Vader just kicks the living crap out of Luke and then saws off his arm. It’s a crucial bit of character development and an awesome scene, and any man can relate to a situation where he did his best and got beaten badly. It shows Luke how far there is to go, how inadequate he is and how hard he’s going to have to work to reach Vader’s level if he ever wants to win.
Nobody would want to see that happen to a cute girl. It would be unpleasant to sit through. Thus the girl character has to be a Mary Sue because she can never lose; if she lost she’d get beaten up and/or injured by the male villain (and thus be less pretty!), and that’s not allowable. Basically the writing sucks because it’s not really possible to have a non-Mary Sue female main character.
According to the above, Director JJ Abrams had no choice but to make the Rey character into a Mary Sue. There might be a good bit of truth to this. But probably, he wanted to make her awesome in her own right, to make up for past oppression and stuff.
But let us consider the possible implications here. It would now seem that it is just about impossible to make women into the common movie character portraying “work, suffer, risk, work, have setback, work, suffer, risk, get close to winning, then win”. The Rocky Balboa character comes to mind. And most people understand that much of good character building comes out of suffering. And Rey did not really do that (scavenging for a living is not real suffering, at least in the movies). Luke Skywalker has to risk and suffer much, and had mentoring by the truly awesome Yoda before he had the character and skills to face Vader. And even then, he pretty much lost twice. In short — nobody believes in Rey’s character; and much of it for this reason.
What other implications might there be? One wonders if as it says above that a primary issue is the prettiness of the character. One can’t allow her to be beaten up and be less pretty. Prettiness is of course a proxy for child bearing capability, and societies normally don’t want that to go to waste (except for modern western ones of course, still, the notion is there). So yes, she cannot be allowed to be less pretty. As for Princess Leia, one wonders if the converse is not now true.
Here on earth, one wonders if women will ever truly be allowed into combat, not withstanding all the hoo-haa about opening combat job to them. Pretty women coming home in body bags will trigger a response that is undoubtedly both visceral and historical. Probably it would stop.
So what to do? Probably nothing can be done. The fantasies in the movies and in the military will continue until such time that it becomes obvious that all of this silliness is just plain stupid. And when we reach that point, life will have been interesting for a while.