Are you okay with Apple not supporting RCS on their phones? As far as I can tell, that strictly worsens your experience as a user.
On the other hand, this doesn’t exactly inspire confidence that it is going to be a polished experience: „Not all RCS functions defined in the standard are offered by every network and every client; only the services that are available to two communication partners are also offered in the client.“ (translated from the German Wikipedia article).
Also, some of my friends and family aren't on those apps and exclusively use SMS/iMessage.