It would have been, but you knew who had tested positive first. If you didn't get that information and only got an anoymised alert, how would you know whether it was the colleague, someone you'd been sat near on a bus or train, someone in a queue to go into Sainsburys etc etc. If it told you exactly when and where the contact was, in what way is it anonymised?
It still doesn’t matter mate, my colleague could have caught it off bobo the clown at a children’s birthday party. They may have caught it in their clinical role. Once they are positive or get an alert from the app they become patient zero and you test, contact trace and so on until you break the chain.
So if you get an alert you won’t know where you got exposed, on the train, asda or of a neighbour, you become patient zero and you need to isolate and be tested before you give it to your nan or your parents for example. It attempts to break the chain, not tell you who gave it you.
From a practical point of view it would be gift, it’s a hard job contact tracing, the investigating, tracking down and importantly explains to people and their family that they may or may not have been exposed. It takes huge resources out of health care that can be better spent, based on my experience above. Data from an app would have been a god send.
