> received emails detailing the work and whereabouts of those employees, including personal matters such as 1:1s, medical appointments and family activities — all without those employees’ knowledge or consent.
Except that that is how Google has designed its calendar system. If you put your medical appointments into your calendar without marking them private then yes, they're going to be public.
So basically, Google seems to have managed to take a feature in its own Calendar App, and the default behaviour of meetings on Google and dressed it up like stalking.