Gold is valuable because it's rare and has a limited supply.
Neither Bitcoin or gold is rare, anyone who wishes to can purchase a Bitcoin or a fraction of it, same goes for gold. Even if it were rare, that is not where its value comes from. A product which is valued solely based on how many people can access it is a bubble and would eventually burst, similar to the tulip mania.
Both Bitcoin and gold have qualities which makes each unique and they are also quite different. The depiction of Bitcoin as the digital form of gold is just a phrase, doesn't potray similarities.
... we can say Bitcoin is digital gold.
Bitcoin is Bitcoin