I actually redirected Shy Guy’s question here, because I locked his other thread. I locked it, because it wasn’t going to be civil since it started with that question. But this thread was already discussing the fandom specific to KYM, and if he had worded it better, then I thought that he might be able to get a decent answer here.
However, it’s very hard to phrase that question in any instance, and it’s even harder to make it relevant to the somewhat different topic here.
To answer your question, Shy Guy (and to try to bring it back around to the topic of Bronies in general,) of course. I’ve seen plenty of comments speaking about in-show lines (i.e. Pinkie Pie talking to Cranky or Rarity being hammy.) It certainly crosses people’s minds at the very least.
But to twist it, think about how unlike ponies the FiM ponies are and how much the characters are like teen or young adult humans. Actually, the only consistent pony trait is their pony shape. Sorta.
Ponies IRL aren’t that colorful, they don’t walk or run like the ones in the show do, they certainly don’t talk or stand on their hind legs in the same manner, they don’t express feelings like them…the FiM ponies are very much human. And the writers (and originally Lauren Faust, creator of this iteration of MLP) put a lot of effort and time into the characterization.
If you were to take the ponies from previous generations, you’d probably get a few people who would be attracted to them, because statistically someone will. Rule 34 has a base in varied sexual interests, to be kind. However, it wouldn’t be as many, because the characterization is more like cartoon horses or very simplistic girls. They aren’t nearly as complex as human women.
Since these ponies are more like anime girls (and we know that people are into their hentai,) you could expect people to “like” those ponies. Because they’re basically more animated (figuratively and literally) older girls/young women. The body type being similar to a pony probably doesn’t come into the picture. A person coming to like the pony shape is likely based upon simple, classical conditioning that makes a person like the body only because it’s attached to such endearing, human adult-like characters.
More simply, the pony shape is the bell. The personality is the food. The “clopper” is the dog (no offense.) The clopper may respond to the pony shape, only because it’s always associated with the personality.
That’s my secret.
I’m always pony.