Breeding does make a difference. We paid a lot for our GSD and he came from a good breeder known for producing good temperaments (our second dog from this breeder, in fact). They have maybe one litter per year and the pups are spoken for before they’re born. I would NOT get a GSD from a pound with kids at home. God bless our president for rescuing a GSD from the shelter. He’s got more guts than I have (and more training resources, lol).
I really enjoy working with herding dogs. Our GSD works cattle and sheep, just like our last one did. I need a responsive dog with enough drive but enough restraint. That requires good breeding.
Our other dog is a spaniel. We got her from a friend that wanted to breed her, but found a hernia and decided the risk was too high for her to pass that on. We gave her a ‘pet home’ and spayed her.
My brother adores Rotties. He and my SIL have always had a female Rottie (they prefer the trainability of the females) and they, too, buy from reputable breeders. None of us have ever been interested in owning a pit or bully type. There are just too many issues. However, if I really liked them, I would do some serious research and find a well-bred one with a good temperament, just like I did when looking for a GSD. I sure as he** wouldn’t get one willy nilly because some shelter worker guilted me into it. What is the saying? With great power comes great responsibility? Yeah, that applies to buying a powerful dog, whether a GSD, Rottie, or a bully breed.