Imagine if Linux was supported by all the big names such as Adobe and Microsoft. Heck, those companies tend to (or at least for a good decent while used to) release all of their brand spanking new features first on macOS before bringing them to windows.
Well, less customisation compared to Linux, but if you’re happy with the UI layout then this is essentially what you’re getting.
I think the phrasing is important here.
If Google’s & Samsungs implementations aren’t compliant with the GSM associations’ standard then I don’t think this is going to work how people are expecting it to. The stuff Google has added to RCS messaging has all been their own implementation of it and not part of the standard, and as far as I’m aware android RCS gets routed through Google’s servers.
I wonder if RCS support is Apple trying to appease the EU with the DMA stuff forcing messaging apps to be interoperable with each other.