I’m sure this has been discussed at length before, but why does GM only offer super cruise on Cadillac models? Is this not a technology that benefits from scale

I’m sure this has been discussed at length before, but why does GM only offer super cruise on Cadillac models? Is this not a technology that benefits from scale, data, and testing? If they have a good product, get it out the door before the competition catches up, right? I’d buy a super cruise Suburban today but will not buy an escalade.