RCS is even less secure than SMS though — it’s unencrypted and by design, Google, Apple and the carriers all have to be able to inspect the content. And the way it’s designed makes it really difficult to have an open E2E encryption standard. So as a result, Google<->Google is encrypted, Apple<->Apple is encrypted, but combine even one device not of the same type in a group chat and it has to be unencrypted.