The nanny dog thing is still coming up. It was a marketing propaganda campaign invented in the 1970s to alleviate the fears people had about pits and sbts. It’s spouted time and time again by lovers of bull breeds who clearly haven’t researched the past of the pets they own.
All bulls are descended from animals bred for blood sport. They have a strong will and need a strong competent owner. There’s no getting away from that fact and encouraging young families to get bullies by crying nanny dog is idiotic at best.
Statistically the majority of fatal attacks have also been bull breeds. The facts is clearly there for anyone to research. So many more than any other breed including GSD/Rotties etc.
I don’t hate any dogs but I really wish people would be more careful. Every time it seems to be the same story. A newly aquired bull type breed, undertrained and under exercised, usually shown aggression before, mostly always young uncastrated males.
It’s really about education. People need to stop putting rose tinted glasses on and claiming any dog can be fixed with love and kisses. It’s not true, genetics plays a huge part in pretty much most of the dogs personality. People don’t buy collies and then act shocked when they want to herd but will happily buy an animal genetically predisposed to animal aggression with a huge prey drive and then wonder why it’s bitten another dog or a ‘prey like’ small child.
Don’t get me started on the constant complaints on rescues either. All day I listen to moanings of people complaining that they can’t get a dog from a reputable rescue because they have small children/cats/don’t have any experience in training a dog or owning a dog and work all day…maybe there’s a reason for the refusal then. Don’t worry though they will just fly one in instead 
My heart breaks for the parents it really does but I think it’s time now for a huge change in the way dog ownership is policed and managed and the legalities of passing on dogs to other people needs to be more regulated.
Oh and just a disclaimer. I don’t hate bull breeds, far from it. I have met many lovely ones.
Would I have one around my dog? No. Would I have one around my child. No.
I wouldn’t object to experienced, responsible knowledgable owners owning them however but how can this possibly be policed?