You’re right there. My daughter has a 150+ pound bull mastiff, he is such a sweetheart I wonder what he would do to protect. He does protect small kittens, lol. Maybe just the sight of him would scare bad guys off.
I had an Irish setter that surprised me one time though.
I have a 135 pound Rottweiler,he’s the sweetest dog to all the cats and our other dogs.But if he senses a threat he turns into a warrior.I’ve seen his war mode once,it’s fierce and frightening.