We don't know. If there is no vaccine ever, and no long term immunity from getting it, then it doesn't matter what you do every country will eventually be infected and have the same death rate. Sweden just happens to be there first but everyone will get there.

Of course my assumptions are big. If there is a vaccine then it is personally worth a lock down to not get it. If there is herd immunity I want everyone else to get it while I personally lock down.