Bluetooth and Bluetooth Low Energy are totally inapprorpriate for the uses governments are trying to put them to because signals are impacted by the radios environment (they bounce around, add and subtrsact in a way thatt makes everything about them non-libear and untransalatable to distance in any meaningful to the degree that they would have to be to work the way they seem to be trying to say it does.
Is impossible for it to be used to ascertain proximity, between two people within the close distance that cause infections (lack of ventilation is likely much more important) also it doesnt work indoors - because it has no way of knowing were it is even with the accuracy of GPS outdoors (where the rick of contracting infection is almost zero as shown by large studies of SARS-CoV-2 infections in China… So when people are in the places where they can be infected, there is no way that Bluetooth devices can with any certainty know where they are as well as a very high risk because of reflections that somebodys Blutooth phone will think it was close to people it wasnt, they could be on the other end of a room or on the other side of a wall or any of a million other things that make it totally unreliable. The only places where it has chance of being accurate (outdoors) the risk of infection is so much lower its basically zero, or close to it in relative terms. If they really want to reduce infection, they need to improve ventilation and keep people further apart indoors. Not doing that is security theater, not likely to help. What they want this for is mass surveillance.