On the other hand, if we don't get long term immunity from the virus we wont get it from a vaccine either. In my opinion there is three paths through this. Two of them depends on immunity. 1. Slow down the spread with soft lockdown, let it pass and get immunity. Will take a long time. 2. Try to severly limit spread with hard lockdown. Either to open up and do lockdown again as necessary or stay in lockdown. Untill vaccine. This is a long road. Optimistic figures is a vaccine somewhere second half of next year. 3. Contact tracing and severe quarantine for infected and contacts until the virus is eradicated. Quick, only possible if the spread is limited. You can't open your country to others until they have done the same or a vaccine is here. The unicorn exit is of course every county doing this and a total eradication of the virus. A country could possibly change track from strategy 2 to 3 if the spread is down really low and contact tracing is in place. Testing without tracing wont do it.

So soft lockdown in maybe a year or more, deaths will be in the 0,5% vicinity, more in some countries, less in some. Hard lockdown in the same timespan as above. Less deaths but will you have any society to return to? If you do hard lockdown for a while and then lighten up you're in situation 1 basically or forced to lock down soon again. Number three is very attractive. Had we all been prepared and had plans for this like South Korea and being island nations with easily shut borders like NZ it would have been simpler. But most countries were not and are not any of that.