It seems that the equine ladies are all very solicitous of his social life.
Hooves and no hands. The creators may have been a little fast on that one. Hands (or at last some prehensile abilities) are some prerequisite for intelligence, aren't they ?
You forget the secret- they do have full manipulative powers- but only off camera. And there was never any notion that they were in any way naturally evolved.
You would not believe the ability horses have to manipulate objects with their lips. We had a horse that could undo the snap-links, open the latch, and let itself out of the stall, from the inside...through a set of bars that were about 4 inches apart. Fast enough that she could do it while your back was turned. I would have been hard-pressed to do it with my hands.
When I draw my ungulates, I include their two vestigial digits as if they were two 'thumbs' that can both oppose the greater hoof. Two thumbs and a great finger.