You can be a bit more charitable than that. Being the acting CEO and then not the real CEO is like dating someone, proposing to them, and then have them get engaged to someone else. Sure you can remain friends but its always uncomfortable around the fiance, the questions "What did they have they I don't?", the whispers, the pity.

People, who are professionals, give room to the new leadership, if they were the former leadership they do that by leaving.