RCS is a nothingburger in Europe, virtually everybody uses WhatsApp (and a smaller group also Signal, etc.). RCS is especially relevant to the US where many people use iMessage and the downgrade path is SMS/MMS.
Whoops my bad then, disregard previous post. Creating a facebook account at once with my national id in addition to my carrier subscription. Gotta love US dependency.
WhatsApp accounts aren't linked to Facebook accounts - well, not publicly - I'm sure they know you're the same person on the backend. You only need a phone number to sign up to WhatsApp. If that wasn't the case, it wouldn't be as popular.
