I think he's full of shit and doesn't have the private keys. I think his end game and next legal battle will be to try to use the courts to force mining pools to recognize Wright as the owner of those millions of bitcoins and give him access to the coins through a fork or some other way ... that even theoretically possible?
Yeah satoshi nakamoto itself must be an anonymous guy which won't reveal his identity that's why he was using a fake name, if this man really invented bitcoin they will not using fake name since his showmanship is high and want to pbe popular among the cryptocurrency users.
So i don't think it's true, but one thing that i trust that satoshi is not a person but a group of people who created the whole blockchain system and they are still involved about bitcoin development until now.