This relationship is pretty similar across different countries. Pick the current point, pick a point with a similar curve, you’ll see differences are at most 2-3x better, often much less so. Much less of an improvement than the quote 20-fold protection against severe disease (95% efficacy)

Those saying “live with it” argue for a removal of NPIs leading to even higher caseloads. If improvement per case is only 2-3x at most then if you go 2-3x past prior peaks the absolute problem is as bad.

I checked the Uk and got 2-3x depending on metric (icu 2x better, hospital and death, 3x)

Denmark is .5-2x better on these metrics from prior peak.

Germany 3x better on deaths (checking prior case peak, December 21st 2020)

Can you find a country which does not have this pattern, where they are actually 10-20x better for a given caseload?

If not, I posit the pattern holds and that this method has some use in predicting future results at a given caseload in a country at European average levels of vaccination, without boosters.

Last year Delta didn't exist. If you want to see efficacy of vaccination, compare incidence among vaccinated and non-vaccinated (which will be about 4x).

Yeah but my point is that people point to relative efficacy when it is absolute reduction which matters. Delta being 2x worse means you need a stronger relative protection.

What do you mean by 4x: relative severe disease protection? That would be 75% efficacy, a marked drop from 95% efficacy (20x protection). I think most of the west still has higher severe disease efficacy than that, though Israel fell as low as 80% pre booster.