> I think it's credible that the interoperability requirements are going to be used to smash end-to-end encrypted messaging
Why and how?
I already use Signal to handle the plain old, almost completely unencrypted text messages. It has no impact on security of Signal-to-Signal communication.
My take on this is that they want iOS to integrate RCS directly into Messages, given tons of other features are already widely supported by the os [0][1][2]. Google Messages (runs on top of RCS) currently only provides encryption when both sides are using Google Messages, so unless Apple and Google create a unified standard it won't be E2EE.
If Signal is forced to interoperate with e.g. WhatsApp, the end-to-end encryption of one or both will have to be compromised. If the integration is forced, then there’s no barrier for either app grabbing all the info from the other in plain-text.
Why and how?
I already use Signal to handle the plain old, almost completely unencrypted text messages. It has no impact on security of Signal-to-Signal communication.