Here is what doesn't make sense about Dorian Nakamoto being the Satoshi behind bitcoin: Here's a guy who code switches during conversations and emails to maintain either the secret identity of an old Japanese man living in CA and playing with model trains, or to maintain the secret identity of a sophisticated programmer who created a proof-of-work system called bitcoin. But then this advanced guy maintaining a secret…
It is probably that not only cypherpunks thought that bitcoin is nice but weird idea, but also Satoshi Nakamoto himself. True, if it takes off, Satoshi will change the world and make some money, but what if it doesn't? Then bitcoin is like bit gold or b-money -- cool theoretical concept, and Satoshi want some recognition for his work(just like Nick Szabo or Wei Dai who used their real names).
Of course there is some chance that bitcoin will succeed, so Satoshi wants to protect himself from government hostility. He knows about Liberty Dollar(don't confuse with Liberty Reserve), he knows about e-gold, and he knows about Phil Zimmermann(criminal investigation related to PGP).
So why does Satoshi need anonymity? Well, he doesn't. All he needs is _plausible deniability_, and he maintains it pretty well.