As you can see the box and its error were used by Helene Kantor to argue that 18th Dynasty artists were uncomfortable with having no ground-line in their figural scenes. While Egyptian art became more impressionistic and mobile (reputedly under the influence of Aegean art) in the 18th Dynasty, she argued that Egyptian artists were so uncomfortable with this idea that their conservatism crept back in at the end of the 18th Dynasty, around the reign of Tutankhamen. This box and a dagger sheath from Tutankhamen were used as her visual evidence for this knee-jerk return to traditional Egyptian artistic conservatism. The idea is that an Egyptian artist could not deal with a back paw of a leopard (or lioness) floating in mid air so they placed a pedestal under its foot.
I might add that this does not actually apply to objects from Tutankhamen's time
The same criticism applies to the conclusions that are then drawn from them. To add insult to injury, you must also factor in that today very out of date academic research is much more likely to be freely available to the public to read and download on the internet than current academic research. This then facilitates the spread of outdated and faulty theories in the media and on the internet.