Samsung messages was using RCS since 2012... Years before Google messages adopted it.
There are others out there that use it but call it by different names like "advanced messaging", "SMS+" etc
Google was the first to add e2e encryption and push it hard though, but if you send a RCS message from Google messages to Samsungs messages app, it won't have e2e, and most likely will be the same with messaging Apple.
But given how much Apple have fought to make it hard (or at least inconvenient) to message between them, and shut down any apps that made messaging between Apple and Android better, this is a big step for Apple
Going after a painting that's behind glass is VERY different to going after the stone henge that has no protective layer, and most importantly of all, has nothing to do with the target of their cause
saying it destroyed the stone henge is a major exaggeration, saying it did no damage is also just as wrong. The English heritage society emphasised that it was only no VISIBLE damage left, however they also said it did cause damage.
It's just like how you can't touch walls in caves because any change in the oils and stuff in our skins can cause long term damage even though there's no immediate visible damage