Never say never. Bitcoin is for now in great shape - it is considered as the best investment of recent years, but no one knows how it will scale.
Gold has a long history, it was always regarded as something precious and valuable for every single nation - there is no country in the world where gold is not appreciated.
Bitcoin from the other hand can be either very successful or in the long run fail to capture people's attention and fail.
Although everything is possible, but still i will like to say that bitcoin is the mother of all currencies and not a single currency has the potential to take its place. I think in present time we cannot expect that bitcoin gold will take bitcoin place. I am sure bitcoin will remain as number one currency of the world for a long long time.