One of the issues that the government will have over doing localised lockdowns is that again the growth areas at the moment are up north.
I know that relatives up north they felt that they were penalised by when "London was high and they were low, everywhere was locked down. When they were high and London was low, they did localised lockdowns."
Now actually I can see the logic each time, and I think they do too. There is an aspect that it spreads better from London outwards. However there is resentment there which will increase if that happens again, and I can see why.
But there was also resentment within the areas. One of my relatives their LA was low compared to the rest of the county, but were locked down with the rest of the county.
But they found that the higher areas were coming into theirs, the perception being, because it was lower. So when they started going up, they said that local people were blaming the out of area visitors (rightly or wrongly). Add into that, that there was an element of ethnicity due to the areas that were effected, so that gave some racial tensions too.
I don't think it would be an easy decision to make unless the local government is urging for it... and if the local government is Tory, then locals will blame the government anyway, and if they're not, will BJ listen to them?
Politics should play no role in this, but I'll be it would.