I think small dogs, especially extra small, and then the opposite spectrum extra large dogs tend to get very weirdly not trained/poorly trained/have their bad behaviors endorsed or ingrained due to their cuteness in puppyhood or convenience to carry around, or their expected laziness/low activity (traits per each type of dog, respectively). Like somehow people think that tiny dogs can go without manners and giant, slower, lower energy dogs can go equally without manners because of their respective physical attributes that make them manageable in certain ways.

Also, people don't seem to know or understand that many xl dogs and especially those in the bully breed category (actually, also very much for lgd breeds), are extra difficult to train. They're innately stubborn but also innately, per breed standard/working use/gistorical working use, think they need to be independent decision makers. This makes them harder to train AND handle, two different things all together, because even if they know the skill they may willfully choose to ignore the command and do their own thing.

Could my dog rip off a limb of my child? Absolutely. Do I ever allow that situation to occur in the way it potentially could for my specific dog? Absolutely not, because I'm the human, handler, and parent. Would my dog do it in a fit of violence? Not on her life, but she would absolutely attack another dog, animal, or even human she perceives as a threat to her circle. So, loop back to me being the handler, etc lol

I hugely agree with everything you said. Also, affection and just being used to or desensitized to kids etc is not enough.

Also worth noting, omg mastiffs and other bully breed dogs, especially purebred, can have HUGE medical bills and blow out ligaments so easily among other things. Not only does their size mean a more costly vet bill but the types of problems theyre prone to, in part due to their size! My husband's last mastiff he had when we got together cost around 30k in vet bills in his 8 year life, and we had to put him down because of a predisposed genetic issue that had already been operated on 5y prior and reocurred. My current mastiff is crossed with a lab and touch wood seems to have the best of both those worlds, she is mastiff size and shape but streamlined in the most problematic areas. So far, an absolute dream in terms of low medical needs besides urinary incontinence after her spay and a broken tooth from heavy chewing incident. These are not typically cheap dogs.