Were you on the vino before you posted this?
Feed all XL Bullies to the tigers? Which tigers?
There isn't a vet in the country who would support a blanket euthanisation of any breed including XL Bullies.
The Rspca and Dog's Trust campaigned against the Govt's ban on the grounds of deed not breed so you wouldn't find support there or any other animal charity either, I suspect.
Fatalities caused by dogs account for 2 or 3 deaths per year if you take XL Bullies out of the stats. 2 or 3 out of 13.5 million dogs. And in the vast majority of those cases, mismanagement of the dog is the cause, not the breed.
In regards to the same breeds you favour, one of them, a Jack Russell, attacked and killed a baby recently. In his summary remarks, the judge pointed out two major contributory factors. One, the dog was forced to live outside. Dogs are highly sociable animals and to make a dog live a lonely life away from the family is cruel and will very negatively effect its behaviour. Secondly, the dog's behaviour on first meeting the baby was to act aggressively but it was still left alone unsupervised with the baby which led to the tragic outcome. The Jack Russell breed is a perfectly sound breed which has been in society for hundreds of years but this particular dog wasn't managed properly. You can't dismiss the human contribution to these tragedies.
And if we're going to start banning things on the basis of death and disfigurement caused by them, why not ban cars? The odds of being in a RTA or being hit by a car are significantly higher than being attacked or killed by a dog.
I don't like the XL Bully breed at all either, but I wouldn't support a blanket euthanasia, that's just draconian.