The big mystery of “The White Lotus’s” second season was supposed to be who died at the end. But all season long, it was continually upstaged by a more urgent one: What the hell was Portia wearing?

Haley Lu Richardson’s fresh-out-of-undergrad character first appeared on-screen wearing a chartreuse-and-aquamarine patterned sweater vest with a choker; later, her cropped Tommy Hilfiger rugby shirt clashed spectacularly with her drawstring linen pants. Then she wore a ... zebra-print bikini top? With a rainbow sweater-shrug over it? By the time she appeared on-screen in a Lee Pipes shirt — directly after a cosmic-psychedelic bandeau-and-flares set befitting of a Spice Girl — Twitter users were all-capsing about it. And what was the crocheted bucket hat about?

Younger and more fashion-conscious viewers insisted the outfits worked; older viewers’ brains broke. “Portia Is TV’s Best-Dressed Character,” declared Harper’s Bazaar, while the New York Times proclaimed “The Misfires Are the Point.” The show’s costume designer defended her style choices thusly in an interview with “W”: “Portia is consumed by TikTok and ‘the discourse.’ ... So we thought it would make sense that she is trying hard, and that she follows the mish-mash trends.”

What much of America was seeing for the first time on-screen, Johnny Cirillo — the street-style photographer behind the popular @watchingnewyork Instagram account — had been seeing on young people in New York’s most stylish neighborhoods for months. “Pre-pandemic, I noticed a lot more monochrome. Top-and-bottom beige, top-and-bottom white, top-and-bottom black. After the pandemic, things got very loud,” Cirillo says. But his photos lately, he says, have been a parade of pleats and ‘90s-style pattern-clashing, “an explosion of hot pinks and electric blues and bright reds” — not to mention more skin. Before, “you didn’t see as many bras as tops, or sheer clothing,” he says.

Portia, in other words, was many Americans’ first glimpse of a Gen Z aesthetic. When society got abruptly sucked into the COVID-19 tunnel in 2020, millennials were still the dominant force in fashion; the oldest members of Generation Z were barely 23, fledgling independent consumers. Now, as many Americans stumble out into the light at the other end, their blinking, squinting eyes are adjusting to the sight of Gen Z assuming authority and relaxing the rules of presentable adult attire, smushing together discordant patterns and colors and silhouettes into chaotic combinations and putting lately-unseen body parts once again on display. On city streets all over the United States, the trendy young people look different; Kylie Jenner wannabes have ceded the habitat to Ella Emhoff disciples. They’ve emerged from the pandemic era simultaneously euphoric and world-weary, ready to both participate again in the world as they knew it before and burn it all down. As Cirillo puts it, “I think people have busted out of their shell.”

Maybe some people quietly felt it happen, the subtle change in the air. But it bowled over Emma McClendon like a gust of wind. McClendon is one of America’s few true authorities on cool pants; she literally wrote the book on them, “Denim: Fashion’s Frontier,” in 2016. So you can imagine McClendon’s dismay this fall when she emerged from her upstate pandemic hideaway, started a new job teaching fashion studies at St. John’s University in Queens and discovered her pants were uncool.

The 36-year-old former curator at the Museum of the Fashion Institute of Technology began class by engaging her students on the subject of denim. Immediately, the ooof of it all set in. Baggy fits, they said, were the ideal; flares, low waistbands, wide legs. And most importantly, enough length to send fabric cascading down and stacking on top of the shoes. Clearly, McClendon’s slim, tailored, cropped-at-the-ankle trousers, her go-to professional look, had been eclipsed by ... well, a multitude of decidedly weirder and more theatrical styles. Listening to her students and looking at their clothes, “I was thinking” — McClendon falls silent for a moment, remembering it — “’Wow, my pants are just not in.’”

Soon, she saw curated chaos all around her. Her students’ clothing choices were harsh, loud, strange; their outfits insouciantly casual, often juxtaposing the skimpy and delicate with the comically oversized. To McClendon, the student body — sometimes even the individual student — looked like a loud pastiche of late-20th century styles. There were miniskirts. Slip dresses. Bra tops, especially paired with gigantic blazers. Towering, chunky lug-sole boots and loafers. Skirts on men, cargo pockets on women. Thrifted items of every color, shape and era. “It’s like a costume for ‘Clueless’ meets a construction worker. In, like, ‘Working Girl.’ And then there’s also a grunge ‘90s aspect,” McClendon says. “It’s a lot of stuff that, a few years ago, if you’d asked me, I would have been like, ‘That stuff’s never coming back.’”

Back in the monochrome before-times — the era of “mom jeans,” turtlenecks, androgynous straight-cut silhouettes and an overall convergence between menswear and womenswear — modest was, for a time, hottest. Even the crop tops were demure. Thanks to that era’s sky-high waistlines, “all you got was that sliver of the upper (midriff), rib-cage area,” McClendon says.

Post-pandemic, it is once again open season on belly buttons. And other body parts. Sex is back in style, and so is gender: Menswear and womenswear have diverged once again, though who wears which can no longer be safely assumed. “What we’re seeing are clothes that typically we would consider hyper-gendered,” McClendon says. “But they’re being played with in a way to eschew gender.” (See: Steve Lacy and Lil Nas X’s love of dresses. Emma Chamberlain’s baggy “dad jeans.” Bella Hadid and Kaia Gerber’s cargo pants.)

Many young people’s everyday styles are put together a la carte from both ends of the gender buffet. “When I wake up in the morning and I’m feeling ... like, provocative or sexy and confident, I would want to wear something more feminine,” says Brenna Gentner, an 18-year-old from Chandler, Ariz., and a first-year student at the Parsons School of Design. When she’s feeling more casual, she gravitates toward more masculine styles for comfort.

On the day Gentner spoke to The Washington Post, she was wearing a red lace lingerie top over a thrifted Ed Hardy shirt. “I definitely wanted to take those lingerie pieces and kind of like, give them a new meaning,” Gentner says. “And be sexy without having to be, you know, secluded to a sacred space.”

Cirillo posits that young adults in America’s urban centers got restless and started taking new risks during the pandemic. “People were revealing a little bit more when they had their masks on,” he says. “It was almost like this secret identity: Well, I’ve always wanted to do this, but I haven’t had the confidence to pull it off.” Then they ditched their streamlined, optimized, safe-for-work silhouettes in favor of daring, one-of-a-kind pieces, often found through thrifting. Which, perhaps not coincidentally, is a practice Gen Z has handily revitalized.

Dressing for exhilaration or to boost confidence — or, hell, just to feel something again — has lately been dubbed “dopamine dressing,” notes Rachel Tashjian, the fashion news director at Harper’s Bazaar and author of the popular newsletter Opulent Tips (as well as the Harper’s Bazaar story calling Portia the best-dressed character on TV). Or as Ditte Reffstrup, creative director of the Danish luxury brand Ganni, calls it, “covid revenge dressing.” Ganni has been working to keep up with a demand for “a sexier look,” Reffstrup says. “So many have a major urge to go a little wild because they have missed out on so much.”

Brands, to their credit, have done their best to keep up with dramatic changes in what consumers want: Ganni announced collaborations with popular ‘90s and 2000s names like Levi’s, New Balance and Juicy Couture. At the first sign of a pendulum-swing back to baggy pants, J. Crew introduced its instantly beloved Giant Chino (made for men but beloved by everyone); Everlane began selling a casual Drape Pant for women (or as Vogue calls it, a “puddle pant”). Both brands confirm that they’ve had trouble keeping the styles in stock; Everlane’s waitlist has sometimes been 6,000 consumers long.

In short, after the pandemic, “A lot of people started dressing in this kind of exuberant and expressive way. Which is how I would very broadly define Gen Z style,” Tashjian says. “Now, even the minimalism is so freaky,” she adds with a laugh; it’s undulating, eccentric, personality-driven. “It’s gone from, like, Le Corbusier to Brancusi!”