The notification appears to be somewhat contextual. Rather than a blanket message sent out to all Apple Maps users, it seems to be targeting people who have travelled internationally recently, perhaps having visited an airport.
This is likely using on-device intelligence due to Apple’s stringent privacy-preserving approach to features like this.
Earlier this year, Apple Maps began showing COVID-19 testing locations to help users get tested if they began showing possible coronavirus symptoms.
The company has also released mobility trends data based on aggregate routing requests which showed the extent to which people stopped moving around in the height of the pandemic lockdowns.
Apple Maps now sends you a notification if you’ve recently been to an airport pic.twitter.com/BJSs2c6CQM
— Kyle Seth Gray (@kylesethgray) July 24, 2020
FTC: We use income earning auto affiliate links. More.