Gold would be more competitive if it could legally be used to buy & sell rather than primarily being a store of long term value.
Anything that adds greater functionality to gold could be a benefit, not only to gold but to society and civilization.
Gold supply, like bitcoin supply, is regulated to a degree by mining. This makes gold in a limited sense, resistant, to manipulation which could destroy value and innovation over the long term as well as limited bar to entry for markets in propping up monopolies and exploitive business standards.
Gold is legal and you can use it on whatever you like. You can use it like an old way of exchanging items and you will choose the item that has the same value with your gold then you can do trade or exchange each other but that is the old way of transacting so gold is not interesting anymore because bitcoin got all the things that we need and that is why people are more into bitcoin rather than gold
You have raised an interesting topic
While gold is certainly legal in most jurisdictions, it doesn't mean that it can't be made illegal one day as it once happened in the US in 1930's. And if the private possession of gold is banned, most gold owners will likely have difficult times and insurmountable issues selling their gold or just moving it from one place to another and hiding it from the authorities. Bitcoin, on the other hand, is virtually invulnerable to such bans, you can trade and move it equally effortlessly whether it is banned or not. In a certain sense, Bitcoin is above any ban that a particular government can impose on it