I really don't know why successive Govts don't stand up to the dog lobby.
To be fair, most people anti-bred ban are against it because they think it's a short term, ill thought out law that is long overdue a proper overhaul that does not result in weird anomalies such as puppies from the same litter finding themselves on opposite sides of the law - because of natural variation in leg length etc.
Most people wanting stronger laws want them because the current law is a short-term, ill thought out law that is not preventing dog attacks to the degree it should or could.
I am not sure there is a lobby that is anti any laws at all. (Except the hunting lobby who continue to succeed in getting their dogs left out of any real controls at all).
These dogs are extremely poorly bred, poorly raised and poorly trained. The result is a temperamentally unstable animal with immense power. It is both the shitty breeding and the training that has failed them.
I'm not defending them - they could all go tomorrow afaiac. But I do think until we rethink dog laws and put greater focus on owner qualification then we will see these dogs replaced with another breed within a very short few years. Take a Cane Corso and have career criminals breed a few gens, like the XL has been bred, and it will kill people (for example).
Successive governments haven't failed to take on the dog lobby (imo); they have failed to give enough of a shit to put time and effort into better, more rounded dog laws. The cynic in me says that's because it's not their 'kind' of pensioners and children dying.