The Google/Apple concept deals with the privacy implications pretty well. I may be misremembering details, but the idea is that everyone's phone stores its own

The Google/Apple concept deals with the privacy implications pretty well. I may be misremembering details, but the idea is that everyone's phone stores its own database of unique identifiers of other devices its come into close proximity to. Then an alert goes out saying "anonymous device XY123 tested positive", and if my phone has that ID in its list of people who may have been close enough to infect me I'd get an alert, but the alert wouldn't tell me who it was who tested positive, and the central system doesn't know who has come into contact with who, it just knows when someone says "hey, my ID is this and I just tested positive" (which is no worse privacy wise than using your real name when going to get tested). As to how gov reacts if/when they know someone has Covid... well that debate will exist in any country where there aren't 0 tests taking place, because "what will they enforce on me if they think/know I have covid" is happening more from people who test positive than from contact tracing. So it's a different subject, but frankly anyone who does have symptoms or a positive test should be staying the hell away from anyone out of decency without needing any government enforcement.