The reason they have been searching for months for a diverse female lead is that they are looking for some real diversity. Hollywood has tons of tons of actors of every ethic or ethnic-mix persuasion, hoards of actors of every sexual persuasion and gender-identity, abundant of actors of every of religion you can imagine. But they wanted to push the envelope and find some real diversity.
They put out a lead casting call across all of Hollywood, seeking Actress who was Republican. Two weeks into the search they thought they finally had someone for the part, but it turned out to be Clint Eastwood in a dress.