The lockdown is far from unobjectionable. Some say this COVID-19 is right about on the edge between clearly favoring lockdown versus no lockdown. The mortality numbers really are not so large comparing to other causes of death, and if secondary human effects are taken into account the decision becomes already very difficult. There are several ways to approach this (with varying degrees of criticism), I think the main ones are 1) Simply evaluating separately human impact (measured in several ways -- all cause mortality, QALY, etc.) and economic impact; 2) Economic-exclusive approach: accept costs compatible with as far as current acceptable QALY costs. Both depend on disease modelling and social dynamics forecasts of course.

1) Addresses criticisms of 'putting a pricetag on life'. To be fair comparing and giving value to ways of life and death is quite difficult, so any simple single measure can be unacceptable to any majority.

2) This approach takes into account already established acceptable trade-offs between economy and healthcare costs. Simply an extension of what we already do: we do not spend all our resources trying to save everyone from every malady, we make trade-offs (e.g. many patients don't receive expensive treatments that could save their lives because of lack of resources). The problem here is indeed how we measure it, you could argue this particular situation begs a more sophisticated approach that can be measured e.g. by QALY.

Neither line seem lead to easy conclusions of lockdown. I haven't analyzed any of them in depth (would require tons of research and experience I don't have), but I think both approaches indeed currently suggest no lockdown except for extreme situations and keeping measures like mild social distancing and using masks.

This calculus seems like something society could more or less agree upon and this would increase readiness for an eventual next crisis too, without destroying our economy or delaying necessary measures due to controversy. I truly believe either epidemiologists (which were the main consultants), health care professionals, politicians or economists alone didn't have the necessary expertise to tackle this. A wide interdisciplinary approach is necessary (which we weren't ready for).