Seems google/apple's push notifications services are regularly queried by state authorities for obtaining user data -- see this german @netzpolitik_feed https://netzpolitik.org/2023/push-dienste-behoerden-fragen-apple-und-google-nach-nutzern-von-messenger-apps/ --
#deltachat only uses apple's push notifications on iOS for "heartbeat" services -- to ensure the app can show messages for their user (and many users are asking for tighter integration). On Android, Desktop and #ubuntutouch platforms currently no push notifications are used or needed, also no heartbeat ones.