Maybe he ran out of scrap to push with :(. Also: no guard on the saw, blunt as can be and standing to the side instead of in front of the blade. Accident waiting to happen.
Standing out of the line of the blade is a good thing. Standing all the way around the side of the saw makes it harder to smoothly push through the cut.
Exactly. So the best spot to stand is to the right of the guard and to push with a stick when cutting long wood, and to the left of the blade when cutting sheets, and to make sure they are supported on the near and the far side so the blade doesn't get wedged.
It gets worse around 25:45.