Bitcoin can never be a substitute for gold. You can't replace Bitcoin with gold just because of the price and the transaction. Because there is no risk in carrying bitcoin, there is a risk of a big loss in case the price goes down to a big . Gold, on the other hand, has been used by people for ages and will continue to do so in the future. If you save gold for the future, the price may go down a bit again, so both Bitcoin and gold are reversible.