It was my understanding the point of the keto diet was to trigger ketosis -- in which your body starts using fat reserves more readily.
But yes, one of the driving factors of "hunger" (when people eat high-sugar foods) is the insulin spike and associated cravings. Cutting out all carbs gets rid of sugar, which results in no more insulin-spike-driven "hunger". But really, all you needed to do to do that was to reduce your sugar intake. It's also quite hard (though definitely not impossible) to load up on lots of calories without carbs. Most high-calorie food is also high in carbs, because refined carbohydrates are ridiculously calorie dense and it's hard to find something that's easy to eat lots of that matches it. You can't really eat a whole tub of butter, but you can eat a whole loaf of bread or plate of pasta.
> aside from abstaining from all your favorite sugary foods
That is the hard work I was referring to. While it might be a slog when you start out, exercise can be surprisingly addictive thanks to the rush of endorphins you get. But you don't need to exercise to lose weight, nor is exercise alone sufficient -- you can't out-exercise a bad diet.