Future of Bitcoin is as strong as it was in the past. Many countries are going to legalize in their jurisdiction. It will maintain it's leadership and no coin as potential to challenge it.
the fate of the future of bitcoin is everyone's question when some new altcoins are eager and are expected to replace the position of bitcoin in the future.
actually I am not as convinced as you are, I believe if there is a crypto currency that is better on its journey and with better platforms and products, then there cannot be a guarantee that bitcoin will continue to be number one.
bitcoin has an updated development, so I don't think that competitors can beat bitcoin in the future. forget about that, the concern is whether cryptocurrency has a long life span in the future, while regulations are still not made and even the government is still more likely to ban to cryptocurrency