Well the worst part is that we can't know and I doubt that we ever will. If he was truly dead, I believe that he would leave in his last will maybe to reveal his identity. Those AI stories ain't that crazy too, who knows... maybe the government created bitcoin as they did TOR project. We can just speculate until one day, possibly, someone who's the real creator(s) of bitcoin comes forward.
Im not sure that a government would have created bitcoin. What would the purpose be? If anything, it would hurt a government, since bitcoin is an alternate currency to the government-issued currency. Unless it was meant to track drug trade, but Im not sure if is possible, since much of the bitcoin code is open-source.