You do realize that the scanning of bluetooth is already in place? For example http://www.libelium.com/products/meshlium/smartphone-detecti... or https://www.cnn.com/2020/04/04/tech/location-tracking-florid...

The contact tracking system does not add anything that is not present for tracking individuals. What it does provide is for two anonymous individuals to determine if they were in contact with each other for some period of time in the past.

The ability to do surveillance to see if an individual is in a particular place at a particular time is neither aided nor hindered by the contract tracing framework that Apple and Google provided.