The robot head is articulated so that it can aim its camera at what the fimographer operating it wants to photograph. The eye/lens rotates so that the camera can be level no matter what orientation the head adopts. some of what you regard as excessive movements may have been the robot’s operator checking out all the motors (while the “hero” footage was being taken) before embarking on a swim to visit the skittish otters they wanted to film with the robot.
Think about it. This is a nature documentary with a limited budget. Making two robots, one only for show, would be a huge waste of resources.
