The point of that scenario was that, if the app takes off it it could quickly turn from a bad joke scenario to one with real impact. Either by Bob taking the r

The point of that scenario was that, if the app takes off it it could quickly turn from a bad joke scenario to one with real impact. Either by Bob taking the reasonable step of self quarantine, unnecessary test + fearful waiting time, or in the worst case the app could be, like it's Chinese equivalent, used to restrict Bob's movement by others at checkpoints. Severside knowledge is pretty irrelevant if an armed guard or angry mob wants you to show the app before letting you get your Sunday brunch.