The metric you are using is bogus and the argument you are knitting is a strawman. If a years worth of patients with respiratory failure arrive in a month then the inadequate hospital system is unable to provide usual care. That's already happened - it's not a matter of debate it's not a future prediction. Two district general hospitals in my part of London - (more elsewhere) - ran out of oxygen. In one of them at peak 90% of beds were occupied by patients with covid requiring oxygen. No other medical care is possible at that point. In order to cope between 7 hospitals we converted 12 other wards to become ICUs. All those ICU beds had patients with respiratory failure being ventilated using anaesthetic machines from theatres. It's no longer possible to provide routine surgery. That's already happened - it's not a matter of debate.
Most other parts of the country locked down at the same time - 2 weeks relatively earlier - and in the absence of an underground and adequate public transport have avoided the worst part of the crisis.
Either the disease is going to burn out - in which case countries with an early and short lockdown like new zealand / australia / denmark / Austria are laughing - or it's coming back in which case - given the failure to build any system capacity outside of ICU there will be further periods when there is no hospital capacity for usual care. The only function of lockdown without any proper control measures - testing and isolation - is kicking the problem down the road. So many other things could have been done. Could have built facility in hotels for pre icu patients needing oxygen - as Vienna planned - to prevent admission to allow hospitals to continue functioning. Ditto for discharge of elderly patients to empty hotel care facilities. Widespread distribution of oxygen saturation meters and roving cars to visit patients in their homes if they deteriorate - like germany and south korea - again to keep people out of hospital. So many things we could be doing. In the absence of these the lockdown is a charade.
7% of the population has antibodies for covid. 15% in London. On average 18% percent of the population develop antibodies to flu.
My guess (and it's just that) - your post is hubris. There is no herd immunity - once this strain is endemic everyone will have their trial over the next few years and will suffer the odds according to their station.
The Tories don't care how many people die - everything they are doing is for show.