Supergirl can't exist post Crisis unless the editors lets his writers hack the work and ignore what Byrne did with the link the Kryptonians had to their world (which is a cool sci fi idea and a good way to stop just that, writers hacking).
Odds are that unimaginative Berganza will let them do just that, though, to please the outdated writers and outdated readers.
Comics are like a Rorschach test; everyone has a different opinion on what they are and can be...
