Upload & Sell: Off
This discussion ignores the fact that lenses like this are rarely purchased outright.
Rent it when you need it. Funny that people think you actually have to buy lenses like this. Nobody buys e.g. a $50k Phantom Flex camera unless they do a lot of super slow motion work. Most tools in this price range are rentals and you pay the $2k a day when you have a job that justifies it.
Same with this type of lens - for most potential users it is a special purpose lens, so it is more economical to rent it it when you need it, for example to take shots like this (yes, that's taken with the Canon, but same idea): Moonwalk
Remember the Canon Canon 1200mm f5.6? A $90,000 36 pound lens available in the 90s? I saw one in use once, at the start of the Indy500, shot by an agency guy. I think it was Allsport or Getty and he told me it was the only one owned by the agency. I think the $18k for the Nikkor only raises a discussion because it is almost close to something people may actually be able to afford, but it is already borderline exotic pricing. If it was priced at $50k, nobody would lose any sleep over it.