Vince Mcmahon literally owns WWE but the board fired him. Of course he voted in a new board at the next election but I dont think it's unheard of boards to vote against their founders. Sam is a founder of openAI even if he never controlled the board, and they tried to take control from him.
Bad analogy. Sam has no stock in OpenAI or any sort of formal controlling interest. His power is solely informal: his own talents and abilities and the loyalty of the other employees. Regardless of the truth of the matters, the episode is a perfect example of the limits of formal authority and how informal or "soft" power can be even more effective in shaping events
The point is that board coups are a concept that people are already familiar with, so its not surprising that they thought of it when this similar situation happened.