You said that Warner roots against the Rams and has left the fans behind. Neither of those things is true even though Warner identifies as a Cardinal. How he has acted is not the same as what you are inferring. But i doubt Warner has it in him to actively root against the Rams. He may be rooting for the Cardinals but he's never been anything but professional with all of his commentating.
Like I said, if you need to project something on to him that makes it easier for you, that's one thing. But what Warner's actually done doesn't line up with what you're saying.
I don't remember Everett as a Saint or Charger. I don't remember Ferragamo as an Alouette, Bill or Packer. Dickerson as a Colt or Falcon. Bruce as a Niner. I'm glad when they show up to Rams games and events and I don't really care if or why they identify themselves with a team. I'll always remember Warner as a Ram and the most amazing season of Rams football I've ever experienced.