It depends on what the definition of the word "IS" is...
Look, rivalries are about tradition and history, with a bit of demographics thrown in...It's more than rooting against the Fish, it's rooting against the whole Miami lifestyle...South Beach, art deco and stone crabs cause me just as much angst as Marino, Csonka, and Cox.
I'm sorry if my "living in the past" does not live up to your standards of fandom. You're saying that the Bills-Fish rivalry is "not the same anymore," when you have no sense of what the rivalry actually "IS."
I know you're the target audience for the NFL...it's proven in the ads I'm force-fed every Sunday. But like many who have already responded, I have to add, that to declare the Buffalo-Miami rivalry dead is pure nonsense.