Disaster just means a bad event, literally ill-starred as in the stars said it was going to be bad. A major crash in the company value (he is NOT getting his $44 billion back), less than half of the company staff size, a data privacy nightmare as the company is failing to comply with government regulations all around the world, a huge hit to revenue (if that's not a bad sign for a for-profit company then what is?), server outages and slow service across its userbase, a drop in userbase (if that's not a bad sign for a social media company then what is?), an interface on a website-driven core product that no longer loads properly for most users (remember all those worthless people you fired?), and a CEO who has publicly stated on record that bankruptcy is a possible outcome he is considering as the resolution to all this....
...that easily fits the definition of a literal disaster.