None of this is to say that Davis isn't making a good point. I agree with her, actually. I just think her comments fall on....not exactly deaf ears, but rather the ears of people who are listening for other things. And I don't think that she's relevant the way she was, oh, 20 years ago. She's basically out of the game, it seems. Although that's partially due to issues in Hollywood with women in their 50s and 60s. Too old to play "hot", too young to play "grandma," at least by Hollywood standards.
Hollywood will pay attention to this sort of thing if it thinks there's a buck to be made. That said, frequent and widespread discussion of this topic, along with things like how often and widely it's repeated, retweeted, reblogged, whatever, gives an indication of how widespread support for the notion is....which in turn tells you whether there's a market there at all. After that comes the question of "But do we know how to sell to this market?" which, in turn, could lead to more female directors, writers, etc., as dudes in suits maybe recognize (especially after a few crappy attempts on their own) that they don't know how to sell to women as a demographic bloc (other than traditional romcoms/chick flicks).
I do think this will change, if only because society is changing anyway. I don't think Hollywood will lead the charge, although it may help to broaden the scope of the message, as it tends to do (eventually).