Would you want an APS-C camera with an RF mount?

Cato1040 wrote:

BirdShooter7 wrote:

How is RF-s even necessary at all? The reason for EF-s was the mirror. That is gone so if there is a lens with reduced image circle the chip in the lens can simply indicate that to the camera to force crop mode when the lens is mounted on a FF camera. I really don’t see any benefit from all these different lens mounts other than to get customers to buy more stuff

Though that would technically work, it might defeat one of the main purposes of an RF-s system: cost. IMO, the main advantages the EF-s and M systems have over the EF and R systems are portability and cost (there are those that don't care about the previous two and appreciate it for the crop factor (like wildlife and sports photographers) but that's not the majority). Using a full frame body that would have enough megapixels to accommodate a 1.6x crop would probably hit the cost factor hard and possibly the portability factor too.

Whether or not Canon should turn M into the R system is a tough one. I've once polled some Canon users and many of them don't see a need to merge the two. One big issue is that M users would probably get upset over their system being abandoned for a similar one. The other issue is that it would cost Canon to start a new system (though it may offer returns if enough users buy into it). There is also the possibility that switching APS-C mirrorless from the smaller M mount to a larger RF-s mount could lead to a slight increase in cost and size/weight due to the larger mount and the longer flange distance though I'm not sure if these would be significant or not.

I do agree with your reasoning, in that it is difficult to determine which way to go.

I think that portability is what would be hit. Not cost. By that I mean they could very simply keep the cost around the same as the EF-M if they keep the same quality and approach. If they produce f1.2 crop lenses they will cost a ton. 
I mean seriously. Take the M6II internals and repackage it in a RF mount body but one built for a crop sensor, and on the same sort of build quality as the M6II. It wouldn't cost more. I am a mechanical engineer. And material cost is never ever a major contributor to cost. So having a body that is a few mm larger in all 3 direction won't impact cost by much at all. Maybe 10-20 dollars more. The initial major cost is the programming to make the body. CNC and moulds etc. But that would cost the same as it was for the EF-M bodies. 
Same goes for the lenses. They can probably take their current optical models, tweak the input parameters to account for the mount (diameter and flange distance) and limit the software from deviating too much. So tweak as minimal a change as possible to adjust the lens design for the longer flange distance. 
So I really don't think it would cost more if they go one to one. However that is not what manufacturers do. RF mound means those extra pins, and also that aperture ring control. They would likely incorporate that. So maybe that might mean a bit more. But even then, they already exist on the RF, and the hardware can just be copied over. 
So cost will come from extra functionality that the RF-S would allow and people would expect. Like a RF-S with out the internal lens profile corrections, and no control ring and such... man people would be complaining. Oh ya.. and those extra pins to use high speed display setting as well.