Curious why you think owners of 2019-2021 would take a loss? I presume many of these owners also benefited from rebates and other discounts.
Some of the 2017s were discounted by more than $40k based on what I heard. Also people who purchased used 2017s probably benefited from those earlier discounts. For a while you could easily pick up a low mileage 2017 for under $125k. The newer cars were also discounted but not by as much. The 2019 and newer cars (first there are fewer of them, they tend not be loaded as were the earlier cars). I suspect that if you purchased your 2017 second hand that you have less money into it.
Having said that there is no reason why you would lose more selling your later model NSX to buy a new one. My bad.