His peg drops under the bench, his wheel is on the ground because it was too low a bench and because he was oppo, the back pedal is being pushed counterclockwise, causing the tire to force the bike to get stuck really hard.
@Pro's riding bmx, it certainly amazes me I find it really hard to get used to a new set up, gettig used to a bmx took me one month an I still never got confident on it. Those dudes jump on anykind of bike like if they were changing underwear