Ilya votes for and stands behind decision to remove Altman, Altman goes to MS, other employees want him back or want to join him at MS and Ilya is one of them, just madness.
Based on those posts from OpenAI, Ilya cares nothing about humanity or security of OpenAI, he lost his mind when Sam got all the spotlights and making all the good calls.
Ilya sees two options; A) OpenAI with Sam's vision, which is increasingly detached from the goals stated in the OpenAI charter, or B) OpenAI without Sam, which would return to the goals of the charter. He chooses option B, and takes action to bring this about.
He gets his way. The Board drops Sam. Contrary to Ilya's expectations, OpenAI employees revolt. He realizes that his ideal end-state (OpenAI as it was, sans Sam) is apparently not a real option. At this point, the real options are A) OpenAI with Sam (i.e. the status quo ante), or B) a gutted OpenAI with greatly diminished leadership, IC talent, and reputation. He chooses option A.
[0]Never attribute to malice that which is adequately explained by incompetence.