> The most important reason for us to remove SMS support from Android is that plaintext SMS messages are inherently insecure. They leak sensitive metadata and place your data in the hands of telecommunications companies. With privacy and security at the heart of what we do, letting a deeply insecure messaging protocol have a place in the Signal interface is inconsistent with our values and with what people expect when they open Signal.
They do have a point though. SMS is insecure, unencrypted and leaks highly sensitive metadata anyway and it needed to go from Signal. You already have the system SMS app for this to use.