Don Lemon, a co-host of “CNN This Morning,” is still off the air, four days after apologizing on Twitter and internally for describing Nikki Haley on the show last Thursday as “past her prime.” His comment, while discussing her presidential bid, seemed to refer implicitly to the Republican candidate’s appearance and age in a derogatory and retrograde way, setting off a public firestorm that is still reverberating.

Mr. Lemon, of all people, should have known better.

After all, Mr. Lemon has himself experienced criticism because of his appearance and pushed back, vocally, less than a month before his dismissal of Ms. Haley. It was only in late January that he went on something of a spiel saying he understood what it was like to be a woman and be judged on appearances, because the same thing had happened to him.

The occasion, back then, was his decision to wear a hoodie with a suit jacket while on the air, which proved such an unexpected sartorial choice for an anchorman that it went viral, creating its own mini-news cycle. Stephen Colbert called out the look, saying he always watched the CNN show but was “a little taken aback” because of what Mr. Lemon was wearing.

“I know they want to add some comedy to CNN, and this is hilarious,” Mr. Colbert said. “How do you report the news in that outfit? How do you talk about tragedy wearing that? Because what could be more tragic than that look?”

Mr. Colbert, who generally wears a suit and tie on-air, described Mr. Lemon’s look as “a high school track teacher who went for a run,” then stopped at a nice restaurant and was told he had to wear a jacket, so he “stole a jacket from an extra from “‘Guys and Dolls.’”

Mr. Lemon responded in turn on his show, though unlike Mr. Colbert, he did not seem to find anything funny in the subject. First, Mr. Lemon noted that it was not actually a sweatshirt he was wearing but rather a sweater with a hood. Then he name-checked Barack Obama’s tan suit and Volodymyr Zelensky’s hoodie as tradition-breaking precedent (though the Ukrainian president’s sweater of choice does not actually have a hood). Further, he noted, “if Trayvon Martin can start a revolution in a hoodie, then Don Lemon can tell the news in a hooded sweater.”

“Would you wear it again?” the co-anchor Kaitlan Collins asked.

“Of course,” Mr. Lemon responded.

Tucker Carlson (also a jacket and tie guy) picked up on the hoo-ha on his Fox News show, calling the hoodie-jacket combination a “cry for help” and inviting Roger Stone, the disgraced former political operative and author of his own “Best and Worst dressed List,” to comment. “Sartorially wrong from every point of view unless you are running for the U.S. Senate from Pennsylvania,” Mr. Stone said, adding a dig at Senator John Fetterman’s favored uniform.

This may be the rare time Mr. Carlson and Mr. Colbert agree on something.

As part of his response to the controversy, Mr. Lemon also defended himself by pointing out that CNN executives had told him he should look “comfortable” and relaxed as a host of the morning show, duties he assumed at the end of last year after moving from the evening news. (Mr. Lemon was not available for comment to The New York Times.) And what says “relaxed” more than a hooded sweater?

Which, after all, was simply the latest in a long line of striking on-air image-making choices by Mr. Lemon.

“There was also never an openly gay man anchoring the news before, and Lemon’s style demands attention, recognition, and respects,” Erik Maza, the executive style director of Town & Country, said in an email. “It’s transgressive in the way it changes our perception of who the person delivering the news should look and dress like.”

As long ago as 2010, Gawker called Mr. Lemon “CNN’s resident dandy.” In 2016, Vanity Fair named him one of their “Best-Dressed Newsmen.” Since assuming the morning role, Mr. Lemon has regularly paired his jackets, often velvet, with sweaters and turtlenecks, rather than the classic button-up and tie, and experimented with all sort of colors, from jewel tones to pale pink.

In February he walked the runway for a Blue Jacket fund-raiser for prostate cancer wearing a navy Michael Kors pea jacket, matching navy sweater and aviator shades, and not long after sat in the front row at the Michael Kors fashion show in a tweed cape/jacket, open-collar bronze satin shirt with matching trousers and suede boots, and more aviators.

Rules about on-air clothing have generally loosened up over the last 10 years. Traditionally anchor men have worn suits and ties while behind their desks (and anchorwomen, jackets), the better to convey gravitas and the seriousness with which they take the information they are delivering, but in 2010 a WNBC-TV anchor dropped the tie in an effort to make the program more relatable and to hold on to viewers.

Today, while CNN has general guidelines for on-air personalities, it does not have an official wardrobe or detailed dress code. According to its studio tour FAQ, the network provides hair and makeup stylists if desired, and anchors “have general guidelines they must follow as far as style and color but do have the flexibility to wear their own clothing.” This is especially so as programs try to set themselves apart, and the value of an individual brand becomes increasingly clear.

But there is a fine line between showing some personality and things getting personal, as Mr. Lemon discovered. And this time, rather than being the victim of old prejudice and stereotype, he was its perpetrator.

As he noted when discussing the hoodie controversy: “I just want to say that a lot has changed. I understand more how you feel when women talk about [how] they talk about women’s skirts and women’s outfits and their hair and their makeup or whatever.”

Clearly, given his comments about Ms. Haley, he didn’t understand quite as much as he thought he did.