Dog breeds have been developed for both physical and behavioral traits through selective and line breeding. You wouldn't bring a border collie on a bird hunt and expect it to point birds any more than you'd enter a golden retriever into a dog fight.
The responsible dog owner chooses a breed for the behavioral traits they desire even more than the physical traits. And they also choose a dog from a responsible breeder that breeds to maintain the breed standard while selecting for health and behavioral tendencies as much as physical conformity. The responsible dog owner then socializes and trains the dog to be a good citizen around other people and pets.
I don't have a problem with pit bulls, but there are a lot of irresponsible pit bull breeders and irresponsible pit bull owners. Being a pit bull owner requires a lot more responsibility than many other breeds, to deny this fact is not helpful to a more nuanced discussion of pits.