They do (otherwise your curve would never end without measures that reduce the reproduction number to below 1) and it's not (only) my calculations, these things (at least in Germany) have been published a short time after the lockdown was enacted (eg https://www.dgepi.de/assets/Stellungnahmen/Stellungnahme2020... - in German unfortunately, number of intensive care beds in Germany was around 30000 at that point so even in the "best case" scenario they look at - 2% of patients need intensive care for 10 days - a curve that does not bust this number extends well beyond the graph which is one year, and not every country has as many ICU beds per resident as Germany has). The "strict measures until we can get back to containment" was also stated recently as the goal by the Swiss authorities ...

Swiss government is releasing some measures this Monday (ie. nurseries are ~half-open) with further reopening scheduled two weeks from now.

The goal is still to get back to containment, from yesterday's press conference: "Koch: Das ist genau unser Ziel. Nämlich eine Situation mit einem so geringen Infektionsrisiko, dass man alle Kontaktketten zurückverfolgen kann. Dann wäre es auch möglich, ein etwas normaleres Leben zu führen. Es ist extrem schwierig eine zeitliche Voraussage zu treffen. Der Trend ist im Moment positiv und wenn wir unter 100 Fällen am Tag sind, ist das Contact-Tracing wieder möglich. Das kann in ein paar Wochen aber auch in ein paar Monaten sein."

Re-opening some things is not a contradiction, as long as you keep the reproduction number <1 you are on a path so that you can contain things. Stricter measures mean you hit them earlier, laxer measures means later but you might not damage the economy as much ... but in any case they said if it flares up again the strict measures come back.

https://www.npr.org/sections/coronavirus-live-updates/2020/0... ('No Evidence' Yet That Recovered COVID-19 Patients Are Immune, WHO Says)

And if that's true, it seems very likely that a vaccine have issues... if an active immune response isn't enough, I don't see how a vaccine would work. I suppose you'd have to administer it in spaced doses like with other vaccines, but that doesn't bode well for resilience against mutations.

Doesn't account for epidemic overshoot. The faster the ramp up the more it overshoots herd immunity. The more people sick at once the higher the fatality rate.

That said permant economic damage will be due to politcial policy choices not due to a two-three month lock down. Consequence of protecting the rentier class instead of businesses and people.