Apple definitely could not have done this because they don't have this data.
But no, a confident blanket assertion is made without providing any evidence.
Agree with you on high rises and false positives, but then again, if air is circulated in the building or everyone uses the same elevators, might be worth notifying them.
https://www.popsci.com/gadgets/article/2011-10/so-um-why-doe...
https://www.engadget.com/2012-09-06-stmicroelectronics-detai...
I think they were sold as a way of not having to expose your location data to government authorities. Also, Apple makes a fair amount of noise about not collecting fine-grained location data and other PII on their servers; as far as I know, at least, they simply don't do the kind of server-side logging that would let them do the kind of historical reconstruction you're describing in your first paragraph. I'm not entirely sure Google does, either, for that matter, even though they keep a lot more server-side.
(Foursquare, of all companies, could probably do it. But only for a too-small subset of people.)
It's very simple: if your ABC company has the ability to 'trace' people, and you allow 'friendly country' XYZ to use it - then 100% of 'baddie countries' will immediately full court press for access as well, with the possibility of banning your tech if you don't.
And then the political/power haggling ensues: dictators actually do have to worry about popularity, so what would it mean to invalidate all the iPhones in Saudia Arabia ... probably not good, so there's that. On the other hand, being able to 'trace everyone', especially my political enemies is also exetentiayly powerful so ...
I don't know what would happen if this were not the case - if this were 40 years ago, we were not as technically globalised and Apple was just selling to US/Canada, we may see different outcomes.
But as it stands, most governments in the world are 'completely untrustable' with the tech, and so it's almost like it renders moot the question of whether Switzerland, Sweden, Japan, or the US can have it and 'play well'.
And to be clear, this is not just a problem of the Apples and Googles of the world. Many more face similar issues, starting with the telcos themselves. The point is that location tracing is something that is routinely done for other legitimate reasons, but the recent pandemic suddenly forces everyone to be specific about how and why we allow it.
Putin wants more power vis-a-vis his proles and if he can strong-arm a company into doing something, he will.
Apple and Google have a certain kind of power, governments do, but most companies have very little flex.
Specifically 'up and comers' i.e. startups must have to face some weird challenges there, certainly in the area of 'content filtering' and government access we are only scratching the surface.
I can only imagine what kind of deals FB has made with various regimes, and he lengths they will have done through to obfuscate it.
The point isn't to figure out where the contacts were. It's to figure out who they were.
I may be misremembering details, but the idea is that everyone's phone stores its own database of unique identifiers of other devices its come into close proximity to. Then an alert goes out saying "anonymous device XY123 tested positive", and if my phone has that ID in its list of people who may have been close enough to infect me I'd get an alert, but the alert wouldn't tell me who it was who tested positive, and the central system doesn't know who has come into contact with who, it just knows when someone says "hey, my ID is this and I just tested positive" (which is no worse privacy wise than using your real name when going to get tested).
As to how gov reacts if/when they know someone has Covid... well that debate will exist in any country where there aren't 0 tests taking place, because "what will they enforce on me if they think/know I have covid" is happening more from people who test positive than from contact tracing. So it's a different subject, but frankly anyone who does have symptoms or a positive test should be staying the hell away from anyone out of decency without needing any government enforcement.
Dragnet location use is vastly more justified for pandemic tracing than for law enforcement. I'm not sure how this could set a worse precedent than we already have. Just trading one for the other would be a boon for privacy.
Between them, they have exact positions of a vast majority of individuals, at least in western societies. They could have done useful contact tracing at the press of a button, even historically, for every major event such as large concerts, churches, night clubs which we know were the most important situations to contact trace. They could have done this with the data they already have.
This would however set a bad precedent on how this data is shared. Law enforcement is one thing, medial tracing is another. So instead they set out to build this BLE tracing toolkit, which is something that at best is intended for future use, when everyone has the requisite hardware and software installed. It wouldn't reach more than a minority of users today which severely limits its usefulness, all for the possibility of reaching into situations such as bus rides, where nobody really knows how contagious these situations are because we simply do not have enough knowledge of the virus yet. Real world measurements are also likely to be noisy (where someone carries their phone in their hand and another in their backpack with a water bottle) even if we could set a hard limit on a safe distance, which we can't.
So maybe we will get something useful in the future, for the price of not exposing the data already available today.
It is amusing that the BLE tracing toolkits were sold as a way of not having to expose your location data to Google and Apple, the exact entities who already have fine grained location data on most people.