This reasoning is the only one that makes sense. Where action taken by the board aligns with logic and any private action done by Sam Altman that could have offended the board.
The story of the board being incompetent to the point of mental retardation and firing such a key person is just the most convenient, attractive and least probable narrative. It's rare for an intelligent person to do something stupid, even rarer an entire board of intelligent people to do something stupid in unison.
But it's so easy to fall for that trope narrative.