I agree on them being unhealthy, but I have to disagree on them being disgusting (taste-wise).

They're engineered to pack as much sugar and fat into a package that feels light to the mouth and dissolves all that flavor quickly. Trying to do that is not a novel concept - take pastries, for example - but with modern technology it's more extreme and is easy to mass-produce.

So, they're a very different food from regular donuts, and they are engineered to taste too good for humans to properly handle. Food like that is why Americans eat too much food.