From my perspective, once the car has a story that affects the title it changes the value. I look at it from the perspective of the future potential buyer, will they pay market price or top dollar for a car that has a branded title? Not anyone that I have met.
I also understand that the value of these cars reach a point so low that even a minor fender bender, which I agree most have had, could and would have rendered the car a salvaged title by the insurance company. I also know that there were many scams in the 1980's where people were cashing out on their cars then buying them back from the insurance company at a large discount. At the end of the day however the title is branded and the value is diminished.