Frankly, the longer the videos get (WRT to the time before the collision), the less I find it appropriate to put loads of blame and shame on the Cessna pilot. The husky merely appears as a tiny glistering dot in a rather "glareful" environment and its position on the windscreen remains quite stationary, with a tendency to move more and more to the pilot's peripheral field of vision (right lower corner).
I tend to concur with DAR here (if I got his point correctly): the main omission has not occurred in the minutes and seconds before impact but on the ground during planning and briefing of the Cub-Cessna duo. Maybe I misjudge that but IMHO the Husky should have been considerably better visible to the Cub than to the Cessna pilot, and an explicit briefing along the lines of "if anyone in either the Cub or the Cessna spots a plane in the vicinity, holler on the radio instead of assuming that the other pilot has seen it, too" might have made a difference.