Originally Posted by Willi Berg
I just see Nolan, if he had his way, not having a direct reference to a character that he might not want to see in MOS. Look how he changed the Robin character so it wouldn't be so overt. I see Nolan wanting to stick with the basics, like he did with Batman, because he wouldn't like these other characters, like a Robin (the comic book version) or Supergirl, that some people find "silly".
I never really had the impression that people have an anti-Supergirl thing going on like they do with Robin. Robin was made to lighten up a dark character, Superman was already "light" when Supergirl showed up so it wasn't exactly betraying the tone of the comics. Plus, Supergirl has Superman's powers and isn't in the same kind of danger as a human sidekick like Robin, meaning it would be more realistic for someone like her to become a superhero.