Heck, in the old days, they often had the opposite reputation. They were once known as friendly "nanny dogs" that were great for children!
Pete The Pup from Our Gang/The Little Rascals was a Pit Bull. Buster Brown's doggie sidekick, Tige was a Pit Bull.
It wasn't until the late 80s-90s that Pit Bulls became the "Killer Death Doggie Of Doom".....I guess people got bored with ripping on Rottweilers, Dobermans & German Shepherds.