I have seen this claim repeatedly, but always without numbers.
I completely agree that the measures have economic consequences, and the economic consequences will cost lives. But how do you know that the number is greater than the fraction of population killed by the coronavirus?
For example, the coronavirus in Sweden killed 0.05% of the population. Also, at least 0.7% got sick, with various consequences. Could you estimate what fraction of their population have other countries killed by the lockdowns? Ten percent? One percent? Zero point one percent?