Other Generations could answer that, we must be dead after 100 years or less, the life of a person is unpredictable so asking something like this is really hard one to give opinions. But I think bitcoin will still exist that long as long as there are people who will still use bitcoin, invest on bitcoin, and so on. Bitcoin could live for eternity, I mean, it won't die because it is decentralize and second is because it is not a living thing.
Everything in this world have an end, and so the world itself have one, so everything that we have will be basically useless if we are going to die, and that is enough reason to answer to what's OP question is.