I do notice that the pulling hear is designed for a pipe to follow it through the ground. A lot of pipe was replaced around here using a similar concept, but the new pipe was size ti fit into the old. I see two situations in the video..

#1 the pipe is buried less than 1 pipe diameter under sand which totally collapses as the cutting head is pulled through. We have no idea how long that pipe runs under the sand. The set up appears to be staged as the pipe daylights into a wood box set into soft sand. That is a big pulling head. The bend radius for a pipe that size to large fot the pipe to follow i into that box.

#2 we see a section pf pipe resting on pallets and connected what I assume is the pulling machine. If that pipe was in fact buried in any number common of substrates, those jagged edges created by the cutter would not be able to flay away like that and would possibly even be pressed back onto place with the jagged edges slicing into the new plastic pipe.

Interesting concept, I just have questions about real world use.