I guess it's possible a pre-internet old school trader "manager" could be suddenly convinced that message boards move stocks, but include the audacity/ego factor and the verbosity of his defense and my money is on the recent grad.
He must have good financial advisors. Even a mediocre advisor would advise him to limit the amount of shares he holds. He is not an investor in the same sense as us, he is assigned to run a company and deliver a profit for the shareholders. Guaranteed that he will not sell every single one of his shares. What is riding on it is his reputation. If he hurts NFLX, he also hurts himslef. ( I know, some of these losing ceo's get even better posts after killing a company.) I see it as him just doing a sensible thing.