Once the high resolution R comes, we will likely see the return of some form of crop or line skipping, unless Canon is still holding back with the R5 and actually has the capability of reading and downscaling what seems to become a 80+ MP sensor.
So that will likely be a camera that has a lesser general appeal for video users compared to the R5.
But the whole idea that a mirrorless camera with great video specs somehow being a disadvantage for stills only shooters is simply flawed.
In a mirrorless camera, everything depends on the ability read and process data from the sensor as quickly as possible. Because the sensor is the source of AF and metering information, tracking information and even the viewfinder content. Those are all aspects that are part of both video and stills. If you a camera was unable to produce 8K 30p 12-bit RAW with AF, it would also be unable to do 45 MP 20 FPS 12-bit Stills with the e shutter. Those are basically the same thing.
Putting a H.265 encoder in the camera is actually something that could be dropped and not affect the stills capability. But it would reduce market appeal and lessen the demand. If that alone would actually safe enough cost to make the camera cheaper despite smaller sales, why is every low end DSLR still equipped with video functionality? In those bodies, that feature makes the least amount of sense, as it doesn't work well anymore for bodies without DPAF and is not necessary for stills shooting at all. Simple. It increases demand to a degree that offsets the cost. There are no downside to having a mirrorless camera that is an absolute beast and using it only for video.