IMO it makes sense to do common sense things like wearing masks, washing hands and social distancing because there's not a lot of associated cost with those actions.
Mandatory lockdowns, however, like they are reinstating in Europe are just stupid IMO. The first lockdowns did nothing to eradicate the virus but they did have all kinds of collateral damage like increasing suicides, drug usage, crime/violence, etc. and of course wreaked the economy. So they did a lot of harm for at best just delaying more virus infections. That's what we've learned.
The common sense approach is a VOLUNTARY lockdown for the vulnerable (i.e, those having other health conditions, the elderly, nursing homes, etc.) but leaving all the other people under the age of 65 or so to go about their normal business who have an over 99% chance of recovery if they get the virus. Anybody at any age, of course, who wants to lock themselves down VOLUNTARILY can do so but let the vast majority of the less vulnerable people just do their thing.
JMO.