It's the same reason it took forever to get Captain Marvel and Wonder Woman, because they all thought that the failure of Elektra and Catwoman meant people didn't want superhero movies with women in the lead role.
Catwoman hurt. A woman as sexy and sensual as Halle Berry, in the role of Catwoman... that's a slam dunk if there ever was one. You would have to WORK to screw that up. But they managed it.