Here is a rule of thumb that will be familiar to many who manage risk in a professional capacity: The time to get creative is when you face a capped downside on the one hand, and an uncapped upside on the other. The time to get conservative is when you face the opposite condition. The reason for this rule is that creative policies almost never work; but when they work, they have a much higher chance of working extrao…
This is a smart observation. The UK is now taking the conservative view because it's the long term view, that this will likely become a recurring seasonal virus (or a one-time virus that keeps knocking on your door until you get it), and therefore there's not much point in a national "lockdown" to "stop" the virus, because as soon as a nation relaxes its lockdown the virus will simply pick up right where it left off.…
(I've been doing the arithmetic for this stuff all day but here goes).
The UK's population is about 66 million. Sixty percent infected is 39,600,000. A 1% death rate (which, per above, you can't escape by "just infect young people" or something, jeesh) implies 396,000 dying. That many people dying, spread out evenly over a year is 1084 people dying per day but 10,840 people arrive sick at hospitals. Which is something the UK surely can't deal with. So with the health care system overwhelmed, the death goes to 5% or more and you have 2 millions deaths, much the WWII casualties etc.
Also, the "herd immunity" reasoning is wrong in the sense that we don't cultivate herd immunity to black plague, Ebola or small pox because they are deadly enough that we containment. Covids is in this special deadly "sweet spot" where it doesn't seem deadly enough to isolate in small area but too deadly to allow to run rampant across a city or nation. The answer that's forced on nation is mass city-by-city quarantine. Harsh but China's Wuhan experience was nowhere near the horrors that this "herd immunity" plan promises.