How effective was the lockdown?
It is clear that there is contradictory evidence on the effectiveness of the lockdown strategy. In the UK it is hard to be sure of the scale of benefits: they range from very few lives saved to a high of perhaps 450,000 lives saved (that is the difference between the 500,000 or so deaths projected by Ferguson et al (2020) (1) on the basis of no change in behaviour and the 50,000 or so deaths that might have resulted in the UK by early June 2020). Figures for lives saved in the UK at either end of that spectrum (near zero or as high as 450,000) seem implausible.
There are reasons to be sceptical of figures at the high end of that scale which puts the saving of lives from the lockdown at several hundreds of thousands: