Clearly some breeds are much more likely to be vicious than others. Me, I'd gradually phase them out, programs to reduce their breeding and certainly not allow them into Thailand.
So many lovely breeds available. My favourite, Border Collie, so smart but need lots of exercise and too friendly to be a guard dog. If people want a dog that is smart but suited to protect, then German Shepherd, Labrador or Retriever.
Why are people attracted to Pitbulls and Rotties? They are somewhat intimidating even if not vicious.