It would still need green bubble treatment as the security guarantees are weaker than iMessage or any of the myriad google chat systems. At its base level it i

It would still need green bubble treatment as the security guarantees are weaker than iMessage or any of the myriad google chat systems. At its base level it is meant to be e2e encrypted but that fails frequently enough that google has to have special UI to indicate the failure, even though they endeavor to minimize how visible that indication is. For group chats (the ones that seem to pop up in examples) RCS does nothing: it isn’t e2e. Group e2e is challenging, which is why it’s still rare even though it has been the behaviour of messages’ group chats since day 1. That said it is mind blowing to me that the carriers specified RCS’s group protocols as anything other than fully e2e. If you’re going to make it a standard you don’t get to half ass it. :-/ Then as others have said, in RCS your keys and account are tied to your phone number. This is not as much of a problem in the US, but in many countries changing carrier means changing number.