While fruits are packed with sugar, eating fruit also comes with fiber. This extra digestion slows the intake of sugar into the bloodstream, and getting fat/unhealthy from sugar comes from to much of it going through the liver. Because you may have too much sugar at a time, the liver needs help from the pancreas, which secretes insulin to store the sugar, which makes you fat.
This is biologically confused. Fructose is processed by the liver. Glucose stimulates insulin release from the pancreas. Sucrose is one glucose and one fructose, but as you might guess from the name, fruits often contain free fructose.
Fiber doesn’t slow sugar absorption by very much. It is better than, say, HFCS, but mostly because you can’t ever eat as many calories as you can drink.
Do you know if there's a good rule of thumb for how different that ratio might be? I do like having some quantitative ballpark to go along with the qualitative texture
You may be interested in the glycemic index [1] which represents how much a particular food causes your blood sugar to spike compared to pure sugar. Based on a cursory search, the GI for an apple is somewhere in the 30s which is way less than a candy bar which can be 70+.
