It’s just an anecdote but I quit a job because the CEO fired an extremely good manager that I worked with. If a company has issues, a good person getting fired can lead to a mass exodus. In my case about half of the developers followed closely after me.
in that case you were losing your immediate manager so your personal circumstances were about to change significantly.
however, in the case of sam altman getting fired, it's not clear that anything that OpenAI is doing is about to change and it's not clear that these devs would suddenly have to change course. Also, it's not like Sam / OpenAI has any integrity anyway - the idea that it's "open" is totally fraudulent.
