If it's "just a cartoon" then why do people give a flying fuck what the characters name is? If your sensibilities are so refined that they are offended by the name of a cartoon character then you just need to lighten up.You really don't understand how business works, do you?
It doesn't matter how you think people should behave, this is just the way things are and everyone whining about it changing should grow up and deal with it.
They're going to do what they can to continue reaching the largest audience and, looking from their perspective, are the parents and children who watch it on television more valuable than the "bronies" who pirate the hell out of the show?
The name change was due to legitimate complaints and it was changed to continue meeting the network standards so it could keep airing. Would you prefer the creators protest so the show loses its license and ceases airing altogether? Derpy wasn't a thing until the fandom and you got your damn shout out. Why do you need to keep getting the same shoutout if you were already acknowledged?