I think Bitcoin will not replace Gold, Gold is real while Bitcoin is Digital, but if it is about price, Bitcoin has defeated Gold ...
bitcoin and gold have more specific characteristics and basically the function is almost the same that is for investment, but there is a difference here people may prefer gold because stored in a long time will be safe and there is a reality. people are more confident with something that looks different from bitcoin that the level of security and risk we do not know and the shape was not visible.