I don't have a iPhone, I use an Android phone, but even I don't use RCS, but then I prefer SMS, it does the job and I don't get a load of bloat on messages sent to me. I presume RCS can be disabled on an Iphone if that is what you want, can Imessage be disabled as well?Along with rcs crap coming to iOS 18, I’ll be turning most of these off.
I don't use imessage on my Mac, for the simple reason it will only recieve message as far as i know from Macs or Iphones.