The government could at a later date decide that all restaurants have to hand in all these identifier lists, regardless of whether a potential covid-19 case has

The government could at a later date decide that all restaurants have to hand in all these identifier lists, regardless of whether a potential covid-19 case has been identified or not. Of course, this could also happen with clear text lists. So I would be better for cases like in the article. I just want to point out that it's not a perfect solution.