Interesting. I started getting the COVID exposure opt-in message a few days ago. I've declined both times it's popped up (it's already too late to be contact tracing, no need). This app is already installed on my phone apparently despite declining to opt-in.
I don't think it will happen or that we particularly need to do it, but at this point, contact tracing (I'm talking about in the US) would be cheap and effective.
Especially if it traced back to likely exposure events.
