This is an interesting discussion to have, but I doubt there are any reliable frameworks to come up with a "true and fair" value. At the end of the day, it only needs one freakish investor down the line who wants that piece of paper from you and is willing to pay 3 times the price. I am sure that most of us here have been shocked at times reading how much people are willing to pay for the weirdest items. One example: First-generation iPhone sells at auction for $190,373, or nearly 380 times its original price

If I had ever thought that this would one day be possible, I'd have stocked up on those iPhones. I believe this things like the paper you mentioned can indeed have value. But how much? I stopped being shocked about collectible items or historical papers and how much they can make you in an auction. To anticipate values is so difficult because as a response some people will collect some electronics out of principle just to realize that those items will never be as valuable as this aforementioned iPhone generation.

I think it could be dependent on the narrative that you yourself could put out in public. If there was an auction of a pokemon card, isn't there huge incentive for the pokemon inventor (company or whoever) to go there and pay an absurd price? Stuff is all over the place in the media and people start buying these cards hoping they get lucky or something.