For Canon to include 8K video in the R1, it would require at least a 45MP sensor. That would mean Canon would be reversing course on catering to sports photographers' preference of smaller file size for faster transfer to the agencies they work for. Getting the image to press first is higher priority than being able to crop deeply or print bus-sized images (at least up until now, anyway). Who knows, though -- Canon might have a trick or two up its sleeve for the R1.
The R1 is way outta my league anyway, so I'm glad I'm not waiting for it. Then again, it might be released by the time my R5 finally arrives!