I'm sure he has always been selfish and self-centered, but he likely always had a sadistic side to him as well, as he seemed to enjoy humiliating and firing people from way back... but now? Now he seems obsessed with getting back at any and all he sees as enemies who want/ed to 'fire' him. He just cannot and could not accept being the one on the other side of the table who was hired and then fired. That is just too humiliating for him. So he will carry his false narrative around in direct contrast to reality till the day he dies no matter what. Maybe he really believes he can create his own 'alternate reality' that way. The emperor with no clothes.....