According to LA Weekly’s Nikki Finke, Warners isn’t interested in making films with female leads. Her source? Warner Bros president of production Jeff Robinov who Finke quotes (through three sources) as saying: "We are no longer doing movies with women in the lead." Finke said that Robinov's sentiment/statement was confirmed by three producers.
This totally explains why the Wonder Woman movie has been retitled Steve Trevor and is now starring Owen Wilson, who has also been cast as John Ripley in Alien 5: The Planet Crashers.