There are other dogs that are as aggressive or even more aggressive than Pitbulls, but the problem is that Pitbulls just don't want to let go when they attack. A pitbull attack typically doesn't stop until something is dead or severely maimed. The two main ways to stop a Pitbull attack are to kill the dog, or choke it unconscious. That's why when they do attack it is so much more likely to be fatal.

We definitely should require all Pitbulls to be spayed and neutered, and make them illegal to breed.

I think a large bit of this is who statistically breeds them and why. They're a popular intimidation breed for lowlives and dog-fighter scum.

Pits can be the sweetest of animals, but I think a large part of this correlation is the simple fact that dealer houses happen to have no interest in killer poodles or pugs to keep rivals and cops at bay.

Maybe part of the reason is they're the most common dog?

The paper in the video linked showed German Shephards attacked the most people (all reported attacks, not just fatal).

Another problem is pitbulls aren't a well-defined breed with clear, "pure" bloodlines. There are a lot of different kinds of "pitbulls." Some pitbulls definitely are very aggressive, some are not at all.

I have a smaller pitbull (adopted from a shelter), and I've never seen her act aggressively toward a person. She is well behaved at dog parks and kennels with free-play with other dogs.

One issue is that the data cited often is collected from news stories with the breed of the dog being guessed at more often than not. This leads to two significant problems. One is that any dog attack that's reported on will probably be severe. Other dog bites that are serious but non-sensational will not be counted. Two is that the dogs breed is haphazardly guessed at by either reporters or involve parties. Simply looking at a dog, especially a mix, it can be difficult to ascertain the breed and so one might just call them a Pitbull as a guess. Although I can't find data I would assume that pit bulls are used more often than other breeds for dog fighting, but I am ready to look at statistics and sources rather than simply confirm my own biases.