Andrew,
The Localism Act wasn't introduced into legislation to protect pubs. It was introduced as a catalyst to seemingly devolve power from the centre and implement the then coalition government's 'vision' of 'Big Society.'
Pubs were just tagged on at the end of it, in fact it mentions, ...' Shops, pubs and playing fields...'
If it was introduced to protect pubs then it has been ne of the worst failures in legislative history, as they are closing at the rate of 27 per week. The reason pubs are closing is that (with a few exceptions) they can't make any money. The business model for a tied pub now, is outdated and belongs in the 1960s, pre all the other distractions that people now have. The offer from pubs in general is just not good enough, but publicans still cling to it.
It is a pleasure to visit a good pub, nobody who is a drinker would argue with that, but they are thin on the ground these days and they are going to be thinner.