Make a new video lightroom for video and concentrate Lightroom on Still Photography
I have been a still photographer for over 50 years and still have no interest in video. I think that cameras should be made for stills and other models be made primarily for video there by making that model the best it can be for that product. We are diluting the camera/software by trying to make hybrids. Both video and still photography will benefit by having software and hardware made primarily for its own purpose.
I'm a firm "still photographer" too, but I feel the video support is at about the right level. Nowadays almost every serious camera is not made for stills but comes with video capability - and some people will use it! So Lightroom should certainly ensure that those video files are properly controlled and managed. The video adjustment tools are minimal and I leave it to others to decide if they are useful, but correcting WB seems sensible.