It's unprecedented and I tend to agree with you that at some point the economic carnage is going to force alternatives, but right now that's the plan. Not the plan they're telling you publicly, but the real one they're planning for and reacting to.
At the end of the day if that's the plan you'll go along with it because the men with guns will make you.
As I've commented elsewhere, an approach using contact-tracing via app and GPS data, backed by widespread testing (millions per week) and small-scale isolation of affected, along the lines of China or South Korea, seems to be more effective.
The US population is going to hate hate hate that one. But it's that or stay inside except for going to the grocery store for the next 12-18 months.
If we don't choose option A, and we don't choose option B, we implicitly choose option C: 20% of our seniors die in a single year. Choosing not to choose is still making a choice. I believe there's a song about that.
The all-cause mortality rate in Europe has been dropping in the past few weeks and is now well below normal levels. To me this looks like people have been overdoing the whole stay indoors and avoid any sort of risky behavior.
Europe is not Italy. Europe has a different population age mix (younger), and broader Europe is not under the same quarantine measures as Italy either.
> "To avoid a rebound in transmission, these policies will need to be maintained until large stocks of
vaccine are available to immunise the population – which could be 18 months or more"
That sounds very much like a "worst-case", afaik German CureVac are right now in the stage of selecting the last 2 candidates for a vaccine, they expect first clinical trials around June/July, I'd be surprised if they are the only ones that far along.
That's not meant to say this will be over the instant we have a vaccine, but finding one is right now the big X factor that makes all estimates veer on the rather pessimistic side.