Although this is by all indications a "well-informed" estimate, it's also the only basis for your strong assertions that roughly half of Americans have already been infected by SARS-CoV-2. How can you suggest the accuracy of the ratio doesn't matter? 7.2 is very different from 4x (which is basically what Dr. Gottlieb asserted in his recent interview). Zorba stated that in his state of OK, the ratio found in antibodies testing has consistently hovered around 2x for some time.
As of late November, about 1 in 3 Stockholmers had antibodies and they literally had no formal controls until late fall? I'm guessing they're still under 50% by now.
One out of three Stockholmers has antibodies—but exposure isn't helping one of Europe's hardest hit countries.
fortune.com
Again, if 1M Stockholmers haven't "achieved" herd immunity, I find it extremely hard to believe America's 330M are getting somewhat close without acceleration of vaccinations. If the 7.2x multiple also applies to L.A. County, then about 65% of my county's residents have already been infected! In theory, the daily confirmed cases should be plummeting soon?
It's ironic that you're now saying testing is diminished, when you said over 6 months ago that American testing capacity is world-leading and IIRC you proudly stated in May? that if a person needs a test in Georgia, it's available. There was a natural holidays drop-off but the 7 day MA has been about 1.6M daily tests for a couple months now:
The COVID Tracking Project collects and publishes the most complete testing data available for US states and territories.
covidtracking.com
Look all I'm saying is "we don't know what we don't know." I'd want more than one CDC estimate to conclude half of Americans have likely already contracted the virus, and dismiss a multitude of serological surveys that have been reported on. Note one thing I pointed out a month ago about that CDC page is they model asymptomatic cases at 15%, much lower than most other estimates. If we adjust asymptomatic cases to 1 in 3, does that boost the estimated ratio of total to confirmed cases even higher? To 9x or 10x?