I've had a lift-off just about as short as that in my Savannah, when it was young and light, and there was a freezing cold, howling SW gale blowing, like i think there was in the video. (It used to blow like that here sometimes in August, before the climate changed...) An observer reckoned the wheels only made one revolution on the ground. (No videos in phones in those days, so no evidence...) But I didn't haul it up at very low speed just hanging on the prop like that guy did. Just as soon as the wheels lifted, I put the nose down and held it in close ground effect, and built up airspeed rapidly then hauled back and zoomed up real steep, with momentum enough to nose over into a safe glide if the engine coughed. (I have horrors imagining the fuel in the float bowls when at that very steep climb attitude at full power.....) Still able to clear an obstacle just about as high as would have by clawing up there hanging on the prop, but much safer. In a real bush situation there's also a real risk of getting behind the power curve while trying to climb over an obstacle with a slow, prop-hanging climb like that, and losing climb angle and settling into the trees.....
That's a 'hot rod' aircraft, like a dragster, probably stripped of all weight, and you could hear the very fine pitch prop crackling even with that load, so it would over-rev straight and level.... Great for show-off and that's just what it is, but really good show-off, eh!
JG