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 ...