The Stretch robot (shown in the article) can't unload a truck. It's not designed to lift itself up and enter a truck. Although, the other robots from BD (shown in the dancing video) might be able to do so.
A truck with some mild modifications (a belt on the floor, for example) could probably queue a full load of boxes/contents to a reachable position for unloading. Stretch looks like it's got a pretty tall/long acquisition range.
Obviously wouldn't work OOTB, but definitely seems doable in some niche truck modifications (and likely little-to-no Stretch modifications).
The Stretch robot (shown in the article) can't unload a truck. It's not designed to lift itself up and enter a truck. Although, the other robots from BD (shown in the dancing video) might be able to do so.