But lets take your numbers as they are. It wouldn't be 5% of all infections, or 5% of all severe infections. It would be 5% of all infections _above hospital capacity_. Health systems wouldn't disappear, they would just not take in more folks, or triage more aggressively. I know you address this in your comment, but it is important to note. Because it greatly changes the emotional appeal for your emotional argument to spell it out.
Don't bring long-covid in to this discussion, there is no real hard evidence that it even exists AND is an artifact of covid.
I'm going off:
Positive tests in the UK yesterday: 52,618
Patients admitted yesterday: 3867
https://coronavirus.data.gov.uk/details/healthcare
That's 7.3%. It's gone up since I last looked, about 1month ago. But I wouldn't call it a true rate as there are plenty of people not getting tested. If half the people are asymptomatic or don't get tested for whatever reason, that gets you 3.6%. There aren't many beds left so I don't think they're admitting many people who don't need it.
I'd be happier discussing a range of anything from 2 to 10% because who the fuck knows. Fair?
To address the marginal vs absolute point, again you are quite right.
I'd actually go a bit further: good triaging would be a bit brutal but it would also mean the majority of deaths were old or otherwise ill. There is a concept in UK medicine called quality adjusted life years (QALY). This tries to mathematically account for "obviously you save a young healthy person with kids over an old, otherwise ill person". Death rates don't incorporate that at all. I'd like to see what the QALY figures are like for covid. I don't think they're public though.
A 1.2 R number (the figure being used for London, again a wild estimate...) gives you a 3% daily growth rate. That means number of infected doubles every 23 days. So assuming we stick with just current measures (reopen schools), your death rate will tend to the hospitalisation rate on a 23 day half-life. Assuming 5% hospitalisation rate (again, try it with your own numbers, I'm not wedded to 5%), the death rate will be 2.75% around Feb 7th. Then 3.5% around March 3rd. Then 3.88% around March 26th etc.
I don't know what will actually happen. And I'd add that trying to extrapolate anything exponential is a fools game. So who knows? I'm merely pointing out there are very possible, very severe outcomes.
Similarly, we have no constitution or bill of rights, so a house arrest law is easy and quick to pass.
The issue with the .5% figure is that 5% of covid patients would die if they didn't receive care. So the death rate is only 0.5% until your last hospital bed / ventilators / nurse is busy. Then it's 5%.
We've fucked about letting more and more people get it. Which is fine because 0.5% and because we're following the "herd immunity" strategy. Unlike Aus that went for eradication. But now, so many people are sick the hospitals are full.
London expects to run out of beds within 2 weeks. Rest of the UK in 3 weeks. Given the 5-6 day incubation period, that means we need to reduce the R number below 1 by Monday in London (where people are densely packed and rely on public transport). You have 7 more days for the rest of the place.
Or we accept the 5% marginal death rate. 5% is pretty fucking high.
Look around your office, your sports team, your family and fields. Pick 1 in 20 to die. And that's 5% across the board. It's higher for your grandparents, your sick cousin etc. Plus you have people permanently disabled and "Long Covid" to factor in.
So having encouraged people to go out, having let people test the rules and find them unenforced, and having done all the easy cheap shit (office worked wfh), the government finds it has to get very strict, convince people it means it this time, and get them to stay home, all in the next few days.
Oh, and the current government was elected by the people most likely to die of this. And the current leader is dumb and lazy. And he's spent the last year promising his party no more lockdowns...