This is being too simplistic. Anyone who understand carbohydrate metabolism will tell you that eating them in excess is bad for you. Excess of anything really. Fats are just another kind of food, there are good fats and bad fats. Saturated fats are the bad guys, but there are quite a few good, and neccessary fats. Fats are not evil.
I don't disagree. I'm very much in the low-fat (but certainly not in the no-fat) school of thought, and I strive to make what fat I do consume to be mostly mono-unsaturated, such as olive oil. And certainly I don't think that an occasional steak will kill you. And of course too much of anything can be bad for you. But I contend that Atkins advocates (or permits) grossly too much fat, and too much protein as well.
One thing's for certain: the argument won't be solved here. But I'll continue my omniverous ways, with an emphasis on vegetables and whole grains; that plan has served me well.