I didn't think they were -that- easy compared to some of the previous E4s, but some of the trainers could just be swept through with a single Pokemon (Aaron, for instance). If they'd been any lower in level, a well-balanced team could have just wiped the floor with them first time through.
I had quite a bit of trouble from Hippowdon, Quagsire and Bronzong (for some reason...?) my first time through, but that was basically due to my team being a little low in the level department.