Looks to me like the flap setting may be "a little" more than usually used for
this type of takeoff, but not enough to be causal or contributing.

Hard to say much about speed from this type of video, but he looks slow.

Could be a problem with the C/S prop. The 182, with the prop at fine pitch
usually has abundant excess horsepower on takeoff. If he set the prop wrong, or
if it malfunctioned it could look like this.

Otherwise, as others have stated here, you'd have to know something about the
density altitude at the time, and the loading of the aircraft, as well as
whether the engine itself failed to develmop power.

GF