I can’t imagine that there is any state actually counting those numbers. That wouldn’t even fly in Wyoming. We have started reporting “presumed“ cases, but they are listed as such, and are very limited. Like COVID symptoms AND a laboratory confirmed case in the same household. If states were actually reporting all people told to self quarantine, the Numbers would be orders of magnitude higher. For one thing, every single person who is tested is also quarantined- so wouldn’t that mean that the numbers of people tested and the number of ”positives“ would be the same? Then add in all the “non tested positives” your doctor told you about, and then we’d be stating that there are more positives than people who have been tested.
It IS true that especially early on, and probably still in some places, many people were/are not being tested and are being told to self isolate for 14 days. That is directly tied to the lack of availability of tests, and the fact that for most people, the results of the test don’t change anything- you’re going to need to stay home and not infect anyone else. Even if it isn’t COVID, we still want people spreading other viral illnesses around, because we have to treat them all as COVID in healthcare.