exposure-notifications-android VS exposure-notifications-server

Not even Google does what Google suggests tho, especially if you look at their https://github.com/google/exposure-notifications-android/tree/master/app/src/main/java/com/google/android/apps/exposurenotification

Googles: https://github.com/google/exposure-notifications-android

Not a small one, but a real-life one, the exposure-notifications-server is usually what I like to recommend, keep in mind that you probably need a bit of Go knowledge and context before looking at it so perhaps it isn't the best introductory project to look at; however I recommend you to bookmark it for future reference.

Here, I can even link you to an article of how exposure notifications work: https://www.google.com/covid19/exposurenotifications/

Google's Exposure Notification Reference Serve is a real life example of what you're asking for.

Which is just a massive misunderstanding of how the contact tracing API works, even if you do believe that it was "surreptitiously installed ... on users [sic] phones".

https://www.google.com/covid19/exposurenotifications/ (“The Exposure Notifications System was introduced in an update to Google Play Services. This update did not automatically turn on Exposure Notifications or enable any Exposure Notifications functionality. Exposure Notifications only works if you decide to opt-in.”) Android 6.0 and above.

Source: https://www.google.com/covid19/exposurenotifications/