The trouble is, this isn't even remotely close to feasible. In order to find a useful proportion of cases via testing, you need to test pretty much everybody wi

The trouble is, this isn't even remotely close to feasible. In order to find a useful proportion of cases via testing, you need to test pretty much everybody with cold-like or disease-like symptoms or maybe even just pretty much everybody, and contact tracing only helps if you have some other way to find most of the active cases in order to trace their contacts. That's why experts in publications like the New York Times keep insisting that the US needs to test people on a scale orders of magnitude larger than any other country has managed, including the ones that are starting to reopen. (Readers don't realize what a big ask this is because the articles carefully don't mention this - most people are left with the false impression that it's just doing what other countries have already managed, and that the only reason the US isn't doing this is because the leadership is incompetent or even deliberately covering up the number of cases.)