The reason for bringing hypothetical figures in should be clear, really. In the first place, other countries have seen excess mortality this year at far greater rates than the UK -- for example, a 53% excess in Mexico (year up to October 11), a 79% excess in Ecuador (year up to October 21st), and even an 89% excess in Peru (up to December 6th) has been reported. Even regarding those as exceptions, you can see large spikes in many countries, such as Belgium, Spain, the US, etc, reporting sizeable excesses in the region of 20-25%.
This leads us to two conclusions: firstly, that a 30% excess in all cause mortality in the year of Covid isn't hypothetical; and secondly, that the UK may have actually come off fairly lightly so far in terms of excess mortality. It's reasonable to suppose that this is, at least partly, because action taken by the Government has kept the excess lower at least than it could have been.
Which brings me back to my question: what, in your view, is an acceptable limit on the number of people dying from Covid before extreme action is warranted to try and prevent it?