I know someone who had an English Mastiff - he was a massive bloke so it was fine. His smol pixie wife took the dog out, it went for another dog and she broke both her wrists being pulled over
my aged mum also fractured a vertebra being pulled off a stile by her male cocker spaniel, it's a risk as soon as you have a strong/heavy dog and a fragile person.
It's bonkers that someone as apparently ouchy and impoverished as Jack got such a big dog, especially if she knew she was downsizing, even after her FORENSIC notebooks full of research. It's my absolute aneurysm.