Earlier quoted context omitted.
RCS has enough features for most people, and it will be pre-installed. After people will realize that mobile operating systems can do modern texting without any crutches from their respective app stores, they will increasingly not bother with them, and that will make Whatsapp to gradually be less and less important in an accelerating pace. Those who actually care about e2ee don't use Whatsapp, because it is closed so…
> if Apple's RCS implementation won't work without carrier-provided RCS Could you explain? If RCS works without carrier support, why would Google rely on carrier support in the first place? (It seems for phone number verification, they rely on SMS. I'm confused.)
https://www.theverge.com/2019/6/17/18681573/google-rcs-chat-...
Apple has so far been quiet about how, if at all, they are going to deal with carriers that have no native RCS support. Maybe they will run their own servers and federate with Google, maybe they will use Google's servers directly, or maybe it simply won't work at all without carrier support. We have no idea yet.
Edit: IMO the most worrying option would be that Apple and Google will make a some sort of exclusive bilateral deal that will make them, and only them, to be able to offer non-carrier-based RCS support, locking out any other operating system vendors from the platform. That would probably have antitrust implications, but enforcement is often slow.