It's actually pretty common.
Lots of people think that their grandfather's "whatever" is worth a fortune. Partly hope/desire, partly some misinformation.
One should be sympathetic.
But sometimes it is beyond that. And some people habitually go there. Whether or intentional or not, it is questionable behavior, especially where money gets mentioned or comes into play.
In the cue world I call these people Cue Quacks.
Like quackery in healthcare, naturopaths, herbal therapists, etc, some are aware what they are doing is wrong and some really think they are right. In the end it does not really matter much to the rest of us, ultimately they are all just quacks.
For the ones truly in the know, it can be very frustrating.
I don't know what's up with the email you got, but it smells like quackery to me.
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