Gold does have one important advantage over Bitcoin:
Gold has been used as a store of value for all of human history, all over the world. Bitcoin is only 13 years old. This is why the market cap of above-ground gold is currently 10x that of Bitcoin. On the other hand, the fact that Bitcoin has grown nearly 200% per year to a market cap of nearly $1 trillion demonstrates that it is rapidly gaining credibility.
Over the long run, I expect the fundamental advantages that Bitcoin has over gold to be reflected in their relative market caps.