Deciding to fire someone in such a questionable and unusual manner is never "just doing their job". Someone made a really poor call here, and is trying to excuse it with accusations and events that never seem to have happened.

That combination, and the fact that it resulted in a major scandal for SE, makes it absolutely justifiable to fire the person responsible.

It's only because the events got out of hand, not because of the action per se. The same person has been doing this for many more cases where it was just fine and this is perfectly clear by the tone of the CTO.