In 3 trips to Alaska I have only come across 2 CGs on generators. One in Chicken Alaska. The other on the Alaska Highway in N BC.
No big deal for us. The best CGs are the provincial parks & Alaska state parks anyway. Neither of them have power. They give more of the Northern Experience being out away from civilisation so you are sitting at night watching your campfire not knowing if something is in the trees watching you & contemplating whats for dinner.
The CGs with services are much like CGs anywhere else.