I mean, I can accept an apology when I can somehow understand the initial intention. In the thread the CEO was answering "but stackoverflow also has public accounts!" to people explaining why this was a very bad move. The guy seemed completely clueless.
It was like trying to explain that hurting people is bad to someone who has just punched you in the face. And this guy justifies his move saying that he has watched a boxing match and that seems a normal thing to do. And then the day after that he finally understand for some reason? The apology is useless because the harm done is too great.