Why can't Canon offer their 1.6x APS crop mode with raw as well as CRaw? It would seem a simple thing to do to me for those that want to take 1.6x crop photos.Raw can only be at the full sensor size.
Is the issue storage/file size? Then hopefully the lower bit rate from the future firmware will assist this issue and then you can crop in post
Maybe Canon could delete pixels in the data flow so that only the 4k crop raw is saved. I guess that is possible. Only option would be 30fps though.
Also, FYI, they already offer 8K raw video, which is a vertically cropped size (hence not full sensor size). They could also offer 4K cropped video with a 2x (width) crop factor if they wanted to.