The Hoof is a prominent feature of pony-related material. However, this symbol is more sinister than it appears.
Let's start with
In this picture, Rarity is confused by the simple task of removing duct tape from hoof. The unspoken assumption is that ponies, with hooves, rather than hands, are incapable of removing duct tape. Whether this assumption is true aside, the implication is far more serious. Humans are rather good at removing duct tape from their hands, by the help of their fingers. Thus, the implied resolution of this picture is that a human savior would come to her rescue. The moral is simple: ponies are incapable of performing even the simplest tasks, and are in constant dependence upon humans.
In this picture, the hoof is depicted as incompetent at using a human keyboard, yet again implying the ponies' biological defect inherent in having hooves rather than hands.
In real Equestria, if ponies have something similar to human computer, the input system, I presume, would look a lot like an audio mixer, with sliders and turn knobs, and maybe some trackballs.
I've yet to see a picture where a human is rendered clueless and helpless by pony technology/magic, despite the rich potential. If you are so inclined, here are some possible prompts to draw from:
A human is trapped on a tree due to accidentally touching the wrong button of the teleportation device.
A human hides after poisoned by the poison joke and turned into something embarrassing.
Then, there's Lyra's obsession with humans and hands. The hand jokes and human obsession jokes are innocuous-sounding, but have you ever seen a picture where the human want to be a pony and have hooves? I drew a picture of that once, and the comments on Derpibooru
are like "Good luck with those not fingers
" "Good luck wiping your own rear end as well.
" "Earth’s better, we got cars, the net and Bacon. But so be it, sometimes its nice to pretend.
So apparently fingers, cars, net, and bacon (by the way, I'm vegan) are better than hooves, magic, friendship, harmony, health, and happiness?
In Imperial China, many Chinese women practiced foot-binding. Foot binding (also known as "Lotus feet") is the custom of applying painfully tight binding to the feet of young girls to prevent further growth.
Women with such deformed feet avoided placing weight on the front of the foot and tended to walk predominantly on their heels. As a result, women who underwent foot-binding walked in a careful, cautious, and unsteady manner.
The woman with bound feet is limited in mobility, and therefore, unable to take part in politics, social life and the world. Bound feet rendered women dependent on their families, particularly their men, and became an alluring symbol of chastity and male ownership, since a woman was largely restricted to her home and could not venture far without an escort or the help of watchful servants.
The hoof, as a symbolism of the pony's physical and mental inferiority, of the pony's status as a pitiable and technologically defective race, a mere plaything of humans, is most analogous to the symbolism of the bounded feet. Round, useless, and awkward, the hooves make ponies incompetent in men's work, make amusing mistakes, helpless, dependent upon the goodwill that men so condescendingly bestow upon them. The picture of the pony, cute, struggling with humans' tools and making adorable mistakes, is a picture as deponifying as the picture of the bounded women, shuffling, unsteady, erotically swaying her hips, is dehumanizing.