Cell phones don’t cost tens of thousands of dollars and have easy ways to get around tracking if you’re really concerned. While I can avoid certain apps on my phone or install a different os, doing something similar for new cars is currently impossible apart from tearing it apart to find and unplug the modem.
I guess what I’m saying is that if the recipient chooses to use Beeper, the chain ends there though… Signal did its job and delivered an encrypted message, and you can’t control that the recipient gave decryption keys to Beeper.
Both Signal and Beeper aren’t doing anything inherently wrong, but if you don’t trust messages passing through beeper servers you need to have that conversation with the recipient.
I think this is an issue for any messenger, not just those tied to the beeper service. E2E encryption only covers transmittal of the message, and you can’t control what the recipient does once they get it… What if the recipient has no passcodes on their phone, no disappearing messages, and the phone gets stolen? Whoever stole the phone now has access to all of your messages even when using a fully E2E encrypted messenger like signal.
If you’re using any messenger for highly sensitive conversations you need to have trust in the recipient. Just have a conversation that they’re either not using a service like this, or like others said are choosing to self host it in a safe manner.
https://voltage.cloud/blog/lightning-network-faq/lightning-network-privacy-explainer/