The thing is, though, Powerpuff Girls appealed to both boy and girls from the start. My Little Pony as a whole has a demographic of young girls, it always has. So for a part of that franchise to have writing and characters that have managed to appeal to people outside of its target demographic is almost like a breath of fresh air. I've seen some episodes of Friendship is Magic, by myself and with my brothers, so I can see where people are coming from when they say that it's good. It indeed is a step-up from the previous generations, and considering that Lauren Faust was a fan of My Little Pony growing up, but wanted to do something different with the franchise, I think this was what she was going for, in some aspects. I don't think she really expected it to be as popular with her male fanbase, but she respects them.
Just because some bad, crazy apples have spoiled the bunch doesn't mean that the entire brony fanbase is nothing but crazy manchildren. My brothers and a friend of mine are bronies, and they're sane about it. They have no desires to dress up as a Pony, nor do they have sexual fantasies about the Ponies or any of those creepy, obsessive things. In the case of my friend, he likes the show because he's a fan of animation, and he likes animated shows with good writing and characters, no matter the target demographic. He also is a fan of Lauren Faust because she's a great writer and animator.
So I totally understand where the sane people are coming from. It's just that unfortunately, every single fanbase has their crazies that ruin it for everyone else. I respect people's opinions about their feelings on the show/fanbase, but it's only when they don't do their bloody research that I have issues with them.