I guess it all depends on the target audience, if you collect signatures and coins, then you’re golden... I personally don’t attribute a premium to an item produced as bullion because the designer signed it; especially in digital format. Maybe if it were a limited run of signatures, like 1 of 1,000 or something, then it would have a value to someone. Anyway, I believed we kicked the poor pony to death!
If it's a real autograph, it could be worth something in a few hundred years. Or maybe sooned if the TPG's are able to lead coin collecting in that direction.
Basically everyone who has ever bought an item from the mint they all came with a COA and on that certificate somewhere is the autograph in autopen of the top dog at the mint. Just like everyone who owns a u.s. note has the secretary of the treasurer, and the treasurer himself/herself's signature.