The whole idea of flattening the curve is to minimize the number of deaths from the virus by not overloading the healthcare system, not to prevent people from getting the virus. No healthcare official said that shelter-in-place, social distancing and wearing masks would stop the virus.

Here on the other side of the big pond, this shift has been officially announced in most countries.
'Running' the epidemy close to the 'health care limit' would still mean: two years or so until some 70% of the population will have caught it (even the worst hot-spot in Germany turned out to have a mere 15% after lifting the lock-down); and it's risky in case the numbers rise again at some point.
With a safety margin for health care of a factor of 2, 5 (Holland now) or even 10 (Germany at present) it will take at least 10-20 years. So this effectively means, and officials say so: We'll try to keep infection numbers (and therefore death toll) rather low for one, maybe two years, with the prospect of getting some rather good vaccine in the meantime. If this fails, we'll have to think of a plan B.