I don't think COVID-19 will get an R0 less than 1 absent a vaccine (or herd immunity because >60% of the planet actually caught it).
Treatments also get a little better with time (e.g. we're not screwing around with hyrdoxychloroquine any more), so later infections are likely to have lower morbidity and mortality. So flattening probably reduces the area under the death curve, at least.
Maybe next pandemic we can try an early crash program for massive testing and see how much better that works out.