I think i have already crossed a topic in this forum similar to this one before. Well, in my own and humble opinion, Satoshi Nakamoto's identity has kept secret so that no one might kidnapped him and force him to run a script that would shut his self-made digital currency. Or maybe, he will be forced to make a new coin similar to bitcoin that would somehow take bitcoin's position as the alpha of all cryptocurrencies.

Well, but who knows? Satoshi Nakamoto is a group and not just one person.