If I don't want to live in a world where only men tell stories about women, I also don't want to be a critic in an environment where we have to argue about whether Kathryn Bigelow has the necessary insight into male friendship to direct Point Break.
Hollywood being what it is, it's inevitable that some male director will argue that his life experience better prepares him for a job than one of his female competitors.
On the second, this argument lets male directors off the hook for having to create compelling female characters.
If women's viewpoints are essential to creating better, more ambitious roles for actresses, then male directors can just shrug off any criticisms of their work for failing to meet that high mark.
After all, they're dudes, so what did we expect? (Not to mention that if a female director gets dinged for her female characters, her alleged failure to represent her gender properly could become an issue when she seeks future jobs.)
The movement for gender equality in pop culture has always had two prongs: improved opportunity for under represented people behind the camera and improved representations of these communities on screen. We shouldn't sacrifice one of those goals at the cost of another.
The scenario I've described could get women more opportunities with little net improvement in the representation of women.
Alternatively, if more male directors were to start behaving like Whedon, and creating textured, compelling female characters, their work would undercut the idea that women's frames of reference are necessary to achieve that result.
The savviest thing that white male directors could do to protect their own jobs in the face of an insurgent diversity movement is to prove that they can see beyond their own experiences and tell stories that resonate with the audiences who want to see their own lives represented on screen.
None of which means that Whedon doesn't have the credentials to direct a Batgirl movie, or that his Batgirl movie won't be absolutely tremendous.
A more equal Hollywood would include both more Joss Whedons and more female directors who receive the same opportunities to attain the same success.