Camaro owners won't be against it either since both platforms have very very similar engine compartments
It is more about the fact that Shadowhawk and those who think like him seem to only be prepared to accept one version of the world, a world at which the Firebird is the pony car centerpiece. Unfortunately, it is a world that never existed, which is why the Camaro was picked over the Firebird for the return.
Without that version of reality, some seem unable to accept that GM, SLP, and performance enthusiasts all over the world have managed to go on with our lives in such a happy and content manner.
I just can't imagine how much uproar there would be had the 4th gen Firehawks actually been a major performance upgrade like the 3rd gens were or the G8 version will be. That would have really turned their world on it's head.