Alright. Let's forget all the vendettas we animation fans have against him. Let's look at this entirely subjectively and logically.
This is the man who, single-handedly, lost both Buffy the Vampire Slayer and Roswell, two of his network's most popular shows, without the short span of a few months. To UPN. I don't know the full story behind Roswell, but Buffy would have been more than happy to stick with the WB. But Kellner senselessly went before the press and absolutely bashed the show--his own show!--and called it infantile and silly. For *absolutely* *no* *reason* *at* *all*. And, due solely to his idiocy, Buffy pulled up stake (no pun intended).
Guess you'd call that "power." But I don't know how anyone on this side of Arkham's gates would even consider honoring him as a Hollywood exec, anymore than one would honor Ed Wood as a great director.