The question is very much arguable; many will present their facts and reasons for why they chose the answer they chose. Currently there is no asset that has proven to be competitive with Bitcoin, so we can say that Bitcoin will sit on that throne for a long period of time.
But we are in the era of change, where new impressive innovations are welcomed and accepted. If in the near future there is ever going to be a new asset that will fill in the gap that many consider to be very important, then there will be a shift in choice, but that's not going to happen anytime soon, not even in the next few decades, but in the near future we should be ready to accept change.
I'm definitely in the line of thought with you, change is constant no one may have thought years back, The 80s inventing a financial system like Bitcoin, even though someone had thought of it, but the technology was not in existence which is the internet that Bitcoin operates with today, "The.com bubble" because Bitcoin uses internet to function. But one thing I'm super sure is that, if we consider the number of years it took the world to migrate from the trade by batter system to fiat moneystery system of trade, and now to digital currency Bitcoin, it's going to take a very long time to witness another innovations and technology in this manner that will supersedes Bitcoin if there's ever gonna another one.