Yes, I think you are right: Satoshi is dead.

I believe that "Satoshi" was a British expat in Japan who thought it'd be a good idea to use the most common Japanese name as a pseudonym for publishing Bitcoin, back in autumn 2008.

For a nicely two years he cared for the project and saw it grow, until, in late 2010, he decided that his task was fulfilled and he didn't want any more attention.
His intention was to sit back and see how bitcoin would evolve.

Unfortunately, in March 11 2011, the Pacific Ocean decided to glide further under Japan's shore, causing an earthquake and tsunami resulting in nearly 16k deaths — one of them being Satoshi Nakamoto.
That made the early end of the world's greatest inventor's life.

Rest in piece, Satoshi, we will miss you.