I just gotta say I'll finally be glad when this can blow over sometime after everyone who plans on seeing it (Whether they have good or bad expectations) have seen it, expressed what they thought of it, and now move on.
I'm on the side that thinks Equestria Girls wasn't really necessary. And I don't like it from a conceptual level that even if it's overall decent, will still ruin the movie for me. But even I know the fandom really, really overreacted to something that's still very much a spin-off and likely have little to no bearing on the events of the main show.
I swear, some of the reactions were so bad that you'd think what happened is they decided that they replaced Season 4 and just went on to make an Equestria Girls series instead. When that's not the case at all.