1) You have not met "all dogs." I'm not particularly athletic, but I am certainly more athletic than some of my neighbor dogs, particularly the geriatric ones. The beagle and chihuahua across the street may have been forces to reckon with in their day, but I could crush either of them today. And today is all that matters.
2) Athletic ability, like IQ and good looks, exists within a population as a distribution. Some people are on the smart end of the curve and others are not. As a breed, pits are on the athletic end of the athleticism spectrum. If you randomly chose ten pits and compared their ability to ten chihuahuas, it is almost 100% certain that the pits could run faster, jump higher, and bite harder than the chihuahuas.
3) Pits are indeed common. The two people I know personally know well (1st cousin and next-door neighbor) who suffered dog attacks that required medical treatment were both attached by pit bulls.
Just found this: "DogsBite.org recorded 46 fatal dog attacks in 2020. Pit bulls contributed to 72% (33) of these deaths, over
16 times higher than any other dog breed."
https://blog.dogsbite.org/2021/06/20...iscussion.html
I don't think pits are 16x more popular than the second most popular dog breed.