You could be right.I'm sorry but I disagree. I think on the R the technology is already 100% mature. I just think their problem is timing:
What if they sold the EOS-1 model now? Little uptake because 1) few lenses and 2) people are just conservative and institutions often plan these purchases a year or so ahead of time. So no or low sales.
Then when a lot of lenses are available, and the camera's been on the market for a year or two... now it's no longer a new camera, and Nikon/Sony come out with a pro body... so again no or low sales.
Instead, by releasing several models at the beginning, just as they did with the EOS 650 and 620 in 1987, they're mostly killing time while they build up the lens line, and letting just enough "bleeding edge" adapters start using the new tech to get the market familiar with it. THEN, in 2020 or whenever, they can release the pro R, and people will know the concept well enough from the early-adopters, and there will be be 10-15 native lenses plus all the adapted optics to choose from.
We shall see.
But I do believe they are still working things out as they did with the 650 and 620 models.