Everything in our life, ever ends and eventually improved. You don't need to be a famous analyst to judge this truth. Turn around and see what surrounds you, and remember how it was before. This is an evolution, there will be no more Fiat money, perhaps no more bitcoins.
This is right. It's all about evolution and technological process. Before light bulbs and electricity people were using oil lamps.
Before cars people were using horse carriages. Only Studebaker saw the disruption coming and made a successful transformation from a horse carriage to a car producer.
And in the financial world, after a century of stagnation, crypto currencies are coming around the corner. Mainly Bitcoin, which will have a huge impact.
Regarding Bitcoin becoming obsolete, I think this is something generations after us may have to deal with, but not us.