Bitcoin not comparable to gold for it is from the nature that's why everything is unique and may not to compare to anything. What I've knew is that gold is from nature. So lets stop comparing thing from nature resources.
Bitcoin was created recently, while gold as a commodity has been around for thousands of years. So, it is impossible for bitcoin to replace gold, but complement each other as investment. Having gold is everyone's desire because it is synonymous with jewelry, its shape is real and there is artistic value. Bitcoin has no form, even anonymous ownership. Therefore bitcoin is irrelevant compared to gold, but "value" can be appreciated.