For Steem to be around 87 years later would require at least one witness running the full node. That person could be anyone. But of course the value of the currency would be zero if just one person would be using it. Chances of just one person using Steem by that time is also close to zero because if there is one, there would be many more.
Posted using Partiko Android
My father was a witness, my grandfather was a witness... :)