I suspect they are like many other breeds, it's not so much the dog but the owner. During lockdown many people bought dogs for company without any thought as to how 'qualified' they were to look after them. One of the most dangerous dogs I came across was a jack russell terrier who hated everyone, including her owner, and nearly bit his nose off. These bully tupe breeds are seen as status symbols by some, or guard dogs. They aren't really looked on as pets. Anyone who gets a dog should be vetted (!) to see if they are up to training and caring for it.