People really don't understand the attack here.<p>It does not matter who is providing the notification service. No amount of encryption (actual E2EE encryption) prevents that ability for a government agency or criminal enterprise to functionally compromise the service to determine which users are getting push notifications from which other users or services.<p>It also does not matter if you use push notifications (which are vastly better for performance by every metric), or polling. Necessarily the intermediary (Apple, Google, Signal, FB, etc) know the origin and the destinations of anything that would currently be a notification. Requiring polling does not stop that.<p>Having lots of different services does not stop it either: the orders given to google and apple can just as easily be given to any other company or organization, and more importantly it sounds like google and apple were only able to say anything because a US Senator explicitly asked them so we have no way to know if any organization that was not explicitly asked is also subject to the same orders. The same applies to a criminal organization compromising such a service, only providers aren't prohibited from saying anything, they're just oblivious.<p>If you are using a service that necessarily involves a third party, that third party can be subject to orders that require them to turn over anything about you or messages you send or receive, or criminals compromising the provider watching the same thing. Encryption (real encryption, not just TLS, not "no one other than you or the provider can access it") can only protect the actual content, the sender and the receiver cannot be protected.