I've seen this language used a few times now. A company's CEO is appointed by, and serves the goals of the board. Not the other way around. When the board perceives that the CEO isn't doing this, they can fire him. That's neither metaphorically or literally a coup.
Especially bad narrative in this case because openAI has given itself a charter (and legal structure that subjects the for-profit arm to the non-profit) that stresses safe and broadly beneficial AI development. If this is Ilya, the chief scientist, wanting to take it back into that direction, from Altman, a salesman, that will not hurt its reputation. (maybe it's stock value)