We don't even know he is alive. Or he is real person. We don't even know if he can access all his past coins. So it isn't threat at all. But let's think if he can do, and just do, cash would be dead.
Well i guess this forum is the proof that he is still out there, as he is the founder of the forum
He (or they, whoever satoshi may be) handed over the forum many years ago already, he has nothing to do with bitcointalk no more.