I'm more dismayed by judgmental, prejudiced blowhards casting aspersions on things they know nothing about, other than how to jump to conclusions and assume the worst, than by good-natured adult male oddballs finding a "little girls' show" to be as charming as it obviously is to anyone who ever bothered to watch it.
I have watched many episodes with my daughter, and they are sweet, often clever, and usually have a quite touching moral about how we should all treat each other.
And John de Lancie (Q on STTNG) plays a (now reformed) villain called Discord, to great effect. His comments during the Brony documentary (was on Netflix, now on Amazon Prime) are great.
Not letting one's kid watch this show just because some dudes like it enough to make a humorous big deal about liking it is shameful. Prejudice bad.
Knee-jerk disgust-happy fear mongers ought to watch it themselves, maybe they'd learn something from the life lessons proffered.