As an user, you would be really stupid to use RCS. It is like giving control to Google over your messages that are usually handled directly by your Telco. Also

As an user, you would be really stupid to use RCS. It is like giving control to Google over your messages that are usually handled directly by your Telco. Also, currently sms is the fallback that works without internet and connectivity. But if you want a real feature full efficient and encrypted messenger, use a dedicated one that has no "relation" with your Telco (and eventually google).