No, they’re not, but Google won’t get them (unless, as you state, they use google’s messaging app) Less Google, more better, in my opinion.
MMS hasn’t been a thing at my provider for years now, so want to send me an image? Use Signal or whatsapp (begrudgingly). I already rarely receive or send SMS, so not enabling RCS isn’t a big loss for me, I don’t get added to Google’s statistics (which they are so very proud off), and I won’t really miss any of its features.
It’s actually really nice given the fps without framegen is playable.
I found it to have a positive impact for heavy titles that run around 40fps without it.
Anything below 30 gives this weird stutter