Worth discussing, but it would take months to deploy the level of testing required. You’d need to test a significant fraction of the entire US population every day. Say 30%, which is probably too low. So we need 100 million tests per day? That’s many months away, as is the miraculous (and privacy issue laden) database you’re talking about. By then, this will all be over and millions dead if we just let it run unchecked. We’re buying time to be able to actually implement something like that. It can’t happen in a matter of days or weeks.