It’s not often that Kate Moss gets overshadowed. In 1992, the British supermodel appeared in a photoshoot for Calvin Klein with Mark Wahlberg. “Good Vibrations,” the rapper-cum-actor’s breakout single with The Funky Bunch, hit No. 1 on Billboard the previous year, but the iconic spread would become Wahlberg’s most lasting legacy from the era.

The 21-year-old appeared in nothing but a pair of form-fitting white boxer briefs, showing off his six-pack abs and considerable bulge.

But nearly 25 years later, men’s underwear still isn’t allowed to show too much skin: In March, Aerie launched a line of body-positive undergarments for men, featuring models of diverse shapes and sizes in an unretouched photoshoot.

That shoot also featured something that remains surprisingly rare—a male model in skimpy blue briefs. In a video released by the company, he’s shown taking out the trash.

If that moment felt weirdly unique for a company that sells to a broad audience, it’s because “sexy underwear” for men too often remains a punchline, evoking the homophobia associated with the eroticized male. We’ve come a long way since the 1960s, ’70s, and ’80s, but our underwear hasn’t.

Wahlberg’s wasn't the first moment that men’s underwear had dared sell sex to male consumers: The muscle mags of the 1950s, and underwear catalogs of the ’60s and ’70s featured beefcakes in tight trunks and briefs.

In 1982, the first ever Calvin Klein underwear ad campaign had featured gold medal-winning pole vaulter Tom Hintnaus resplendent in a pair of tighty whities.

But until Marky Mark, the brand had struggled to make designer underwear fashionable for the everyday man.

“We were repositioning Calvin's men's underwear line, which at the time was a relatively small business,” Neil Kraft, who previously served as the company’s senior VP, told Ad Age.

Kraft and his boss saw Wahlberg on the cover of Rolling Stone and knew he would be perfect to help Calvin Klein crack the men’s underwear market. “[H]e had a natural likability,” Kraft said. “I think it came through in the print and it came through in the TV.”

Following the campaign’s groundbreaking popularity, sales grew “exponentially,” both for Calvin Klein and other men’s retailers.

In the more than two decades since, men’s underwear has become a billion-dollar business. Sales figures from 2014 show that the international undergarment industry brought in $110 billion, and brands like Calvin Klein were a major part of that success. In 2014, the company earned nearly $3 billion in total revenue—while the boxer briefs Wahlberg popularized remain its biggest product.

But as much as Calvin Klein changed everything, things also have stayed the same. The company has continued to lag behind Hanes in sales, which reported record numbers in 2015: It raked in $5.73 billion around the globe.

Hanes’s products look like men’s underwear has for decades—garments so massive they could be hoisted like a flag on a cruise ship.

On Amazon, Hanes’s best-selling line is the Tagless Tartan Boxer (no. 4 overall), which is designed to cover up even the slightest hint of genitalia. It’s followed by the slightly more flattering Ultimate Dyed Boxer Brief (no. 6). Both rank higher than any of Calvin Klein’s products.

The continued success of Hanes offers a fairly stark contrast to Andrew Christian and 2(x)ist, which use sex to sell underwear. Andrew Christian, the Glendale, California-based clothing company named for its chief designer, is the clear successor to Calvin Klein.

His brand sells fashion jockstraps, which act as push-up bras for one’s package. The typical Andrew Christian model is Marky Mark with a spray tan, the kind of guy who wouldn’t look out of place on the set of a porn shoot.

Andrew Christian’s advertising luxuriates over the impossible physiques of hairless twinks lounging by the poolside. As if to hammer the point home, one of the company’s most popular lines is called “Trophy Boy.”

As much as it’s selling underwear, Andrew Christian is selling a lifestyle, and it’s easy to figure out who the brand’s core demographic is: gay men.

In a 2015 video from YouTuber Michael Rizzi, straight guys had no idea what to even do with Andrew Christian underwear. They appeared anxious and even uncomfortable at encountering them.

“Initial thoughts?” one man confessed after trying on a pair. “Shame.”

Another said, “There’s a lot of skin going on.”

The consensus appeared to be that the men surveyed would wear the garments if their girlfriends asked them to. After all, many admitted it looks pretty good.

What’s behind straight men’s discomfort toward “sexy underwear?” In a 2007 essay for Out magazine, Mark Simpson—who famously coined the term “metrosexual”—says that briefs, particularly male swimwear, have long served as a symbol of “gay pride and exclusion.”

Even as male celebrities like David Beckham, Daniel Craig, and Cristiano Ronaldo have flaunted their chiseled physiques by wearing Speedos in public (the trend of sportsmen exhibiting their bodies he calls “spornosexual”), Simpson notes a persistent strain of homophobia when it comes to the sexualized male form.

He writes, “Speedos on a non-gay beach are the surest way to earn yourself angry stares, abuse, and plenty of room for your beach towel.”

A notable case of what Simpson calls “Speedophobia” arose in reaction to the sight of scantily clad gay men cavorting on the beaches of Cape May, New Jersey, in the Sixties.

In 1969, Philadelphia magazine reported that “their public displays of affection, particularly among men wearing women's bathing suits on the main beach, turned off the townsfolk.”

The Cape May City Council responded by banning Speedos from its beaches and erecting signs around the tiny resort town that read: “PROHIBITED: the wearing of skintight form-fitting or bikini-type apparel or bathing suits by males over 12 yrs.”

Today, men have continued to associate the male bikini with homosexuality in ways that are often negative. In 2014, Jesse Colter was booted from a Kentucky water park for wearing a red Speedo, after reportedly being called a “queer” by officers on duty.

Three years prior to that incident, the UFC actually banned competitors from wearing Speedos during matches, after fighter Dennis Hallman wore a lavender bikini that read “Training Mask” after losing a bet. “I've never been so embarrassed being in the UFC,” president Dana White said at the time.

An even more famous example involved former New York Yankees baseball player Derek Jeter, who allegedly pulled out of a deal with a Swedish underwear designer over its marketing.

During a 2015 lawsuit, the company alleged that Jeter had an issue with the way the product was being sold. “[Jeter] demanded that [Frigo] not market to the gay community and states that he did not want the Frigo brand to be ‘too gay,” the company claimed during court proceedings.

The underwear’s complicated design, which includes a crotch pocket and strings, owes a lot to companies like Andrew Christian. As Vice’s Matthew Leifheit notes, Frigo is “really, really flattering from the side.”

If our relationship with what we wear down there retains a whiff of homophobia, professor Eric Anderson, who lectures on masculinity and homophobia at the University of Winchester, offers a compelling reason why: For a very long time, all forms of male undergarments were viewed as shameful.

“For men in the ’70s and ’80s, the showing of underwear was highly embarrassing, if it were visible above your waistline,” Anderson told the Daily Beast. “There’s no need for designer underwear, because your underwear was designed not to be seen.”

Film critic Alonso Duralde agrees. In an interview with NewNowNext, he explained that through the history of cinema, male undergarments have rarely been viewed as sexy or the men in them desirable. “Men’s underwear was the punchline to a joke,” he said.

Although seeing men in briefs was common throughout the 1970s—in movies like Play Misty for Me or Midnight Express—Duralde claims that the trend in recent years has been toward boxers.

To wear briefs is to be unmasculine and kind of a sissy. In Wild Hogs, the socially awkward Dudley (William H. Macy) memorably sleeps in his tighty-whities, the kind one might picture Screech wearing.

For men, the act of wearing underwear is about performing one’s gender—which means avoiding anything perceived as feminine. The same is true of any other kind of clothing, including skinny jeans or a messenger bag (often called a “man purse”).

Anderson believes that this is because for many men, heterosexuality is extremely fragile. “Straight men who have a desire to be thought straight have to prove and reprove that they’re straight,” he said. “The way that they can do that is through proving and reproving masculinity—in an orthodox sense.”

However, according to Anderson’s research, things are changing. A decade ago, Simpson’s term—the metrosexual—symbolized a new kind of man.

“It began as a male New Yorker, good looking, thin, probably wearing fancy clothes, didn’t care if people thought he was gay for wearing fancy shoes,” he said. “The fact that it ended in ‘sexual’ was the key—it was the first time men could say, ‘I’m not gay, I’m metrosexual.’”

Today he feels that—among young men—that label is becoming increasingly unnecessary: “It’s so accepted that they can wear better clothes and they can pay attention to their bodies.”

As Anderson is based out of the U.K., he admits that there might be some “cultural lag” when it comes to decreased homophobia in men’s fashion. There’s evidence, however, that he’s onto something.

The Underwear Expert, a online-based company that acts as an “underwear of the month club,” reported last year the greatest share of its clients (27 percent) preferred briefs to boxers and a majority (54 percent) favored low-rise underwear.

Andrew Christian has repeatedly claimed in interviews that so-called “gay underwear” is for everyone. “The new generation of men, straight or gay, are much more liberal and don’t care how something is labeled,” he told Gay Star News in 2013.

That has yet to translate, however, to the revolution in men’s apparel promised two decades ago, when Marky Mark first dropped his pants.

Straight guys, however, have a great deal to gain from embracing sexy underwear: challenging our hang-ups around men’s fashion will create a society that lessens the stigma and shame too often associated with expressions of male sexuality.

If nothing else, there’s a simpler reason men shouldn’t be afraid to try on Andrew Christian: It’s pretty hot. They might even be surprised to find they like it.