No, that likely has nothing to do with the why. It might be one effect of such a long sentence, but I suspect it has more to do with you charge with the crimes you can “prove” and see what sticks. There’s no guarantee of guilty on any charges. Charging someone with many crimes increases the chances of at least one guilty verdict. Of course, it also has other potential impacts, too. People make assumptions about people who are charged with crimes, and they make assumptions when someone is charged with A LOT of crimes. Prosecutors could certainly use that to their advantage.