I hazard you that there's little to no market for things that are solely "highly memorable," especially politically polarizing ones. Most people don't want to own a Hitler Youth knife, for example.
I hear ya, but I think 50 years is wildly generous. I give it 20 years before they're entirely gone except for a few novelty chasers. It's the Yugo of the 21st century, except at luxury prices, actually, then maybe like combining a Yugo with the Cadillac Cimarron or the Pontiac Aztec. Garbage in every way that won't survive a human generation.
I wonder will they run or be fixable in 50 years. Not just the big battery, but every other such component too. In the end DeLorean is relatively simple car and you could even install different engine in it if you have to.