When he says that they 'flip[ped] to being judgmental and self-righteous,' he is simply saying that he's upset that they stopped supporting him and refused to agree that everyone lacks self-discipline. Remember, he mocked "Saintly" Brandon for expecting better of him. Anyone who thinks he should've been a better husband and father is judgmental and self-righteous. Anyone who thinks he shouldn't have been a bully and an asshole is judgmental and self-righteous. If you're not with him, you're judgmental and self-righteous.
As for doing things differently, it's like Kim said: the thing he would have done differently is to try harder to keep his supporters from learning that he was cheating on his wife with prostitutes and is generally a shitty person. It must rankle him that it's become so difficult to bully people and shut them down.