23Sha-ger I think this discussion is pointless and useless. Because in North America they use iMessage mainly, or RCS, nobody else does. Europe/Asia? Whatsapp, etc.
So the reason the only few carriers fully suppport it is..American ones. This is not a conspiracy, just an adaptation. You guys still use inches, 110V, etc.
RCS is an international standard created by GSMA, which is a global trade organization to represent all mobile carriers worldwide. In fact, it's based in London. RCS is the replacement for SMS. So whatever people would like to belive, RCS is coming for you. It's going to be deployed everywhere.
https://en.wikipedia.org/wiki/Rich_Communication_Services
You can see in the article in Wikipedia, that there are already carriers that have deployed RCS in India, Japan, Belgium, Canada, the UK, Malaysia, Japan, China, Greece, The Philippines, South Korea, Spain, Russia, Slovokia, Switzerland, Hungary, Romania, Mexico, Albania, Sweden, South Africa, Australia, and Norway.
That hardly suggests it's just a US thing.
There are also a lot of businesses and services that only send out messages via carrier based messaging, i.e. SMS and soon RCS. So the idea that people can fully escape this is false.