I do think he legitimately believes he's doing the right thing though all throughout, which maybe makes it more scary.
Sorta like how Mark Zuckerberg seemed to truly believe in Facebook's mission and wound up having all sorts of negative externalities for the world. Mark Zuckerberg just isn't quite as effective as Sam Altman, and it's easier to be suspicious of his motives.
Not to say that psychopaths are necessarily bad. Peter in Ender's Shadow turned out great!
But it does seem dangerous for 1 person to hold so much power over the future of humanity.
Sam Altman's reasoning for him having all the power, I think, is that “short timelines and slow takeoff is likely the safest quadrant of the short/long timelines and slow/fast takeoff matrix.”
If you believe that and believe that Sam Altman having complete control of OpenAI is the best way to accomplish that, everything seems fine.
I'd personally have preferred trying to optimize for long timelines and a slow takeoff too, which I think might have been doable if we'd devoted more resources to neglected approaches to AI alignment–like enhancing human capabilities with BCI and other stuff like that.