Bitcoin has a limited supply, yet it is very volatile and even though Bitcoin is becoming more expensive day by day, it creates a new ATH every four years and then drops more than 50% from that price. But in the case of gold, there is no supply limitation, gold is mined constantly, yet only the price of gold keeps increasing day by day, its price drops very little. So since gold can be mined unlimitedly and its price only keeps increasing day by day, Bitcoin will never surpass gold in terms of marketcap. However, both Bitcoin and gold are very popular, one in the physical world and the other in the virtual world. Gold has been accepted as a powerful asset by people for thousands of years, but Bitcoin has only been around for a few years. So there is no way Bitcoin will be able to surpass Gold.
The thing is that gold is being sold many times more than the actual amount that exists.
There are companies that offer you to buy parts of gold, while they keep and store it for you.
This is called digital gold, and many countries have companies offering this service.
You have to basically trust that these companies have your gold.
With Bitcoin though, you don't have to trust. You can simply verify if your Bitcoin is at a specific address.
There's no need for a third party.
