If it's one person, I can imagine he had an accident, was jailed or got murdered. If it's a group of people, that's much less likely.
Up to the next 10 years! If I dare make a guess for the Bitcoin price 10 years from now, it's going to be anywhere from $10 to $10 million. In the past 8 years, Bitcoin went up in value ten thousand fold. The growth will eventually have to turn into an S-curve and slow down. You may quote me on this 10 years from now
I think I brought this up a while ago also.
Someone was saying here that a lot of the writing looks as if it’s from one of the original bitcoin development team (might have been schildbach) anyway my thought is that the team used to run the account, maybe schildbach and Sirius and potentially theymos, and then they each had an account anyway and thus made the forum more secure by splitting their ways and locking the satoshi account.