Android (the Android Open Source Project) itself is not the Problem. It's the lock-in ecosystem that Google tries to establish with the Google Services Framewor

Android (the Android Open Source Project) itself is not the Problem. It's the lock-in ecosystem that Google tries to establish with the Google Services Framework, Play Store and the like. What is missing, is an open and privacy-friendly alternative to GSF. Without GSF we don't have efficient push notifications (Firebase Cloud Messaging), a geolocation provider, a maps API etc. Personally, I have been using microG (https://microg.org/ https://microg.org/) instead of GSF on my phone for many years now. However, that is still just a partial solution. While it does its best to be privacy-friendly and does not have any integrated tracking / analytics like GSF, it still has to use Google's servers for push notifications, thus tracking is still possible to some degree.