That was amazing but I don't think I would like to be on it

There is only a drop on one side. Shelves on two sides, retrieval mechanism on the third.
Normally, it's all automated. Zooms up, extracts the shelf contents (they showed the extraction mechanism running), then returns to ground level for the staff to extract the relevant box. The rest of the shelf contents can then be put back by the robot.
The personnel platform is normally only used for maintenance such as cleaning the shelves, and I bet the robot runs at a lower speed when that is in use.
