Upload & Sell: Off
Those growing up in the digital age tend to believe newer is always better. The rapid product cycles of computers, phones, etc., has indoctrinated them into the uber consumer fold. I can recall when people wanted early production because they thought they were better! Perhaps production was slower and more careful out the gate and accelerated with later copies, resulting in more IQ variance. And then there are lenses like the EF 50 1.8, not made since 1990, people are willing to pay a premium for over the current version due to metal mount, distance scale and generally better construction (plus they seem to work forever).
Personally I'm most concerned about condition, not age. I saw a lens only a few months old a PJ friend of mine used that looked like he hammered nails with it (probably because it belonged to the newspaper). Much rather buy an older lens owned by a gentleman amateur, used only on vacation, Christmas and graduation.