And Bernard, you missed out on the real reason they scream so loudly on him.
It's simple, and you touch on it slightly. The film "The Passion of the Christ" was the story of the death of the Lord Jesus Christ, told as per Gibson's serious take on Scripture. Mel did so without making Him sleep with Mary Magdalene (DaVinci Code, Last Temptation) or making Him gay, like some bizarre liberal play which makes the claim. So, by telling a conservative story, telling the central events of the Christian faith without irony or insult to those of us who believe, he did something unforgivable.
This, like Fox Derangement Syndrome, was the formation of Gibson Derangement Syndrome. How dare someone have a non-liberal viewpoint? They were sooo thrilled to see him fall.
I make no apologies for his drunken behaviour or statements. They were wrong. But like you said, he apologized. But in combo with the film, it was another example of "See, those conservatives are all like that."