By Margaret Sullivan / The Washington Post

Give Chris Matthews partial credit for his apology on his way out the door Monday night. In his abrupt and unexpected farewell, the MSNBC host acknowledged his history of what he called “compliments on a woman’s appearance.”

Such comments were “never OK,” he said, and he was sorry for making them. I appreciated this wasn’t one of those mealy-mouth “sorry if I offended you” apologies; though it still seemed to miss why it’s a problem when a powerful man emphasizes a women’s sex appeal in a professional setting, the way it diminishes and objectifies.

But this casual sexism wasn’t at the heart of why he had to go. One of the most prominent and well-paid hosts in the cable-news game didn’t listen, didn’t do his homework, and treated politics as a game in which noisy confrontation was a necessity. The problem was less about green-room boorishness and far more about what you could see and hear on the air; especially in recent weeks, but also going back a long way.

For years, Matthews was a harsh and misogynistic critic of Hillary Clinton; once calling her a “she-devil,” and attributing any of her success in the 2008 presidential primary to the fact that, as he put it, “her husband messed around.” More recently, his comparison of Bernie Sanders winning the Nevada primary to the “fall of France” to the Nazis was a horribly offensive gaffe given Sanders’ Jewish heritage and his having lost family members to the Holocaust.

But for me, an occasional member of the “Hardball” audience, there was something worse.

With his reported $5 million annual salary, he wielded enormous influence. For many years, he had the power to sway public opinion on the crucial topics of the day. Not infrequently, he failed the main test of someone in that role. He was ready to offer his own views, but not prepared to hear those of his guests or to bring deep knowledge to the conversation.

Frequently described as “bombastic,” and certainly an excitable yeller, Matthews had a tendency to ask a question, and then, just as his subject was beginning to answer, interrupt, asking it differently or inserting his own opinion.

His interview with Elizabeth Warren last month was a memorable case in point. The topic was whether her rival presidential candidate, Mike Bloomberg, had really suggested to one of his employees that she “kill it,” when he found out she was going to have a baby.

Matthews insisted on arguing the case as if he were Bloomberg’s defense attorney, portraying the episode strictly as a “he said/she said” situation in which — who knows? — either side could be lying.

He interrogated Warren: You really think Bloomberg is lying? Why would he do such a thing? Warren responded, when she could get a word in, that she believed the woman. She pointed out that pregnancy discrimination in the workplace is a real thing.

Matthews, for all his intensity on the subject, was unprepared and seemingly unfamiliar with the well-circulated reporting that included a named eyewitness who backed up the Bloomberg saleswoman.

To wit: “The Washington Post interviewed a former Bloomberg employee, David Zielenziger, who said he witnessed the conversation with the saleswoman. Zielenziger, who said he had not previously spoken publicly about the matter, said Bloomberg’s behavior toward the woman was “outrageous. I understood why she took offense.”

That kind of corroboration takes the complaint out of the “who knows?” realm that Matthews’ argument depended on.

But the “Hardball” host apparently hadn’t done the reading. He seemed to want a confrontational interview with Warren no matter what the underlying evidence might be.

For NBC brass — whose recent record on dealing with issues related to sexism and misogyny has justifiably come under fire — this was all too much. And Matthews’ becoming a punching bag for comics John Oliver and Trevor Noah in recent days couldn’t have helped. Something had to give.

Was there some other huge shoe about to drop, a huge scandal of some sort? More likely there would have been a constant barrage of other, similar complaints. His resignation puts a pin in that.

I don’t buy the idea that Matthews, 74, had to leave his post because of his age. There are plenty of men and women in the public eye — in media, in politics and many other realms — whose age doesn’t, and shouldn’t, hold them back. (Think, for example, of Georgia Congressman John Lewis, who is 80, or, in Hollywood, the 77-year-old Harrison Ford.)

Mere age doesn’t keep anyone from being informed, enlightened and effective at their work. And after all, Mathews is downright youthful compared to most of the candidates remaining in the Democratic presidential field.

No, the problem with Matthews was not about the accumulation of years. And it was not purely about “compliments.”

It was about being flawed at the central part of his job; not in the green room but right there on the screen.

Margaret Sullivan is The Washington Post’s media columnist. Previously, she was the New York Times public editor, and the chief editor of the Buffalo News, her hometown paper. Follow her on Twitter @Sulliview.