If you disagree I’m not sure why you wouldn’t sell all your coins right now.
5x btc price or 5x $$ price?
I believe there will come a day in the fullness of time where it will cost 5 bitcoins/the equivalent value in whatever currency to acquire a funded Casascius 1-bitcoin graded 69, 70.
This seems laughable now but eventually they will come to be seen as royal treasures, Crown Jewels of private and museum collections. It might be 50 years or 100, but these will be wonders to behold someday. The supply will steadily dwindle until there are just a few hundred scattered across the earth
Could happen but I don't think premiums will ever be that high. If BTC drops to $100 in 50 years, then yes. If it's the reserve crypto currency, then no way someone will pay $500k (example) for a $100k worth coin.