Rarity approves of this.
I've been searching a (very) little and only found this article. Nothing about actively discouraging bronies, just that they aren't that big a consumer group. To give an example of the accuracy: "The group included four "Pegasisters," as the small minority of female bronies sometimes call themselves". I never heard of 'Pegasisters', and I think I know a bit about the fandom.
Also there's the weird statement "the majority of adult viewers are still overwhelmingly female". Females watching a show for girls? That's crazy!
Awww, ninja'd