Hmmm, this is just like saying "Anime is for kids" but look at all the gore, sexuality, and other rated 18 stuff anime can do.
So defying gender roles, I agree in some point but the part I most agree with is "I know not all Bronies are like this, but there are a decent few." That is true because not all bronies are like that and some pegasisters are also into violence. What comes to our mind when we talk about "men"? Let me see: sports, guns, fitness, violence, masculinity, personal hygiene, money etc. A show that is intended for girls, it can also produce scenes where boys can also enjoy the show. (Besides the pretty ponies and their lovely butts showing all the time.)
The show must be aiming for G since it's General Viewing and it aims for everyone.