One of the rhetorical reasons that has been given that targeted help could not possibly work is multi-generation households. I live in such a household with an at-risk person, and if anything, lockdowns make the multi-generation household problem worse. The problem being that people need to eat, and when everybody is locked down, deliveries become unavailable, so somebody has to go out to fetch food, increasing the risk for the household. We're not just talking about a bottle of milk and a loaf of bread delivered by a neighbour or a volunteer, we're talking about a full weekly shop. The solution to the multi-generation household problem is that for those households that really can't rearrange to minimise risk, the whole household should self-isolate and let the rest of the community proceed as normal.
Optional isolation and furlough for those who chose it because a family member is at risk would be much better than what we have now.
Or set up places where people can go and be isolated for a couple of months while the virus circulates. The government is doing that very successfully for illegal migrants that come on boats - several hotels are full of them. Given all the resources spent on lockdown, it's inconceivable we couldn't build up a good system of moving people out to protected places, with comfort and dignity. Of course that would be too calm, public spirited and decent for our rulers who prefer panic and submission.
