I am also, like all of you guys, disappointed with video capabilities of 6D2 (also using 80Ds AF points array in FF camera which makes it too narrow in viewfinder is also big no no for stills, they should better use 7D2 65 points system and spread it wider over sensor), but my biggest frustration with this camera is that same old soft 1080p. If they had sharp crisp, high bitrate 1080p I wouldn't care at all about 4K as even now, for me 4K serves for cropping and exporting to good quality 1080p.
Now thinking about this, was there ever Canon DSLR with good quality (sharp) 1080p (besides RAW ML) ?