I would normally try to be polite, but when you see someone write something that is total BS, what can you really say?
So you really believe that Canon deliberatly didn't use stacked sensors in all those cameras becuase they knew that in a few years they would put stacked sensors in the mark II or mark II versions? Or could it possibly be that Canon did not want to sell the R for $4,000 or more, and the R5 for $5,000 or more or the R6 for $4000 or more...I think you get the idea. Also you seem to be forgetting that not all photographers care about rolling shutter 'cause they aren't shooting BIF or sports. And perhaps most obviously, you can use all those cameras (except the R) for BIF and sports, and experience both high FPS and no roilling shutter by using Elec. First Curtain or Mechanical shutter. Rolling Shutter is not an issue "we didn't know we had," it is a minor issue for a very small percentage of camera buyers, in all likelihood.