Not to quibble too much with most of your criticism, but this one seems minor and trivially solved:
> this does not allow the screener to differentiate between "has COVID-19" and "had COVID-19"
As a policy matter, this doesn't rule out the use of the test in a pandemic management protocol at all, it just changes how it needs to be administered. For example it might require that people who are antibody-positive have a standardized note confirming recovery (in Contagion, this was a cute electronic bracelet).
The critical requirement is that we detect unknown positives, and this test would do that.
> people who are antibody-positive have a standardized note confirming recovery
How do you prove recovery if you were never proven sick first?
As an example, I had all the symptoms of Covid in late February, the same severity many people in my age group described, yet was never tested since our health authority dropped the ball and claimed community transmission wasn't a thing back then.
If I tested positive for antibodies, would I get treated like someone newly infected? The only way to prove recovery is to prove you have antibodies and don't have the virus, so we'd essentially have to test every single member of society.
There are different subtypes of antibodies that you test, some that emerge early in infection and others that emerge later. The current understanding is that the later emerging antibodies being positive generally indicates that you are not only recovered but also immune from the virus and can donate your own convalescent plasma to be used as a drug for people with the infection. If you test positive for early antibodies you are assumed to still be undergoing the course of the infection.
I also don't think this particular test is an antibody test? It seems that this test detects viral particles based on:
"The most proven and ready to scale technology is based on surface plasmon resonance. It’s able to detect even a very small number of viral particles, which is very important because we want to detect everyone who is contagious"
(6th paragraph in the "A third solution" paragraph)
> this does not allow the screener to differentiate between "has COVID-19" and "had COVID-19"
As a policy matter, this doesn't rule out the use of the test in a pandemic management protocol at all, it just changes how it needs to be administered. For example it might require that people who are antibody-positive have a standardized note confirming recovery (in Contagion, this was a cute electronic bracelet).
The critical requirement is that we detect unknown positives, and this test would do that.