We have seen the future of European fashion, and it is California.

Peering out from behind the curtain of a long lockdown, designers in Paris and Milan seemed unanticipatedly hopeful during the digital shows this past week. It was not so much that they were willing to forgo the inimitable theater of the fashion show as ready to embrace the accelerated alterations in everybody’s way of doing business forced on us by the pandemic.

Being indoors, onscreen, casual to the point of forgetting to put on our hard pants has affected us all, not least designers.

“I was doing all these Zoom meetings, and I didn’t have the garments I wanted,” Alessandro Sartori, the Zegna designer, said last week by phone from northern Italy. What he needed was lightweight things suited to the new exigencies of the workplace. What he had was summer linen jackets in what he called “vacation” colors.

But we are not on vacation, are we? Though we may be working 10 feet from our beds, we still need uniforms that draw a clear distinction between labor and leisure.

We need something along the lines of a formula the men’s wear consultant Josh Peskowitz once proposed as the basis for a distinctly California style when he ran Magasin, the influential (and lamented; it closed in 2019) Culver City store in that state.

Take a comfortable shirt, and trousers, and add something tailored — a bomber, a windbreaker, a chore coat. Or, swiping a cue from the guayabera, that most elegantly casual of masculine uniforms worn throughout the Caribbean basin, simplify to a mere two pieces. The result is something that, while as presentable as a suit, is not one.

The pursuit of the un-suit turned out to have allied designers whose names are seldom seen in the same sentence. When Miuccia Prada showed a loose, dropped-shoulder version of a chore coat or a boxy three-button jacket worn over a snug-fitting sweatshirt, she wasn’t just experimenting with designs intended to function as, the show notes said, “straightforward, unostentatious machines for living and tools for action and activity.”

She was also making unexpected common cause with Véronique Nichanian at Hermès, whose collection — shown in a film by the experimental director Cyril Teste that replicated the vibe of that electric moment backstage when models dress in first looks — was detailed at the achingly refined level of precision you’d expect from a venerable luxury goods house. (To wit: a ribbed sweater with all-but-invisible leather insets.)

Despite that, Ms. Nichanian’s collection remained easeful enough to hold its own with clothes from, say, Second/Layer, a young label in Los Angeles that has a lot to teach the old guard about how to dress a generation that has never worn a suit and tie.

California felt like an uncredited collaborator in many collections. It was there in the gorgeously gnarly shirt prints that the Berluti designer Kris Van Assche extracted from his collaboration with Brian Rochefort, a sculptor who works with ceramics.

Mr. Rochefort, one of the legions of artists who have transplanted themselves to Los Angeles, traveled the world in the days before quarantines to visit volcanoes, caves and sinkholes. He was seeking inspiration for works that frequently resemble magma samples from the core of Planet Skittles.

California was there again in spirit in a Rick Owens show titled “Phlegethon,” after one of the five rivers that in Greek mythology flowed through the underworld. (Styx, Lethe, Cocytus and Acheron were the others, just so you know.)

The Owens presentation, shown on the model Tyrone Dylan Susman, ended up being something you might term health-goth. It fused the sort of funky layering and proportions you would spot on guys in any surf town along the state’s 840-mile coastline to elements of the designer Larry Legaspi’s futuristic death-metal costuming for Kiss.

“I basically make cutoffs and T-shirts,” Mr. Owens, a native of Portersville, Calif., said by phone before his presentation went live online last week. “European complexity meets California simplicity — that’s my gimmick.”

California was also a presence in an Isabel Marant collection shot at the Centre National de la Danse on the outskirts of Paris.

Watching the presentation of a video showing two young models racketing around within the corridors of this Brutalist structure felt like watching two pretty stoners who forgot where they left their car in Parking Structure No. 6 at the Third Street Promenade in Santa Monica. It was a true Reyner Banham moment transplanted to the present.

And the clothes were, like so much of what is being designed now, based on simple overlapping pieces that reflect the exigencies of a changing and often fickle climate. That and the fact that one of the few clear ways to mark the progression of a day, a week or a month anymore is by adding or subtracting a layer.

A critic for Vogue.com referred to the Marant collection as “L.A. meets the Marais.” Yet the low-slung trousers with rolled cuffs, the low-waist flight suits, the waxed poplin trenches and the fuzzy sweaters looked to be no more inherently French than the French Laundry, Thomas Keller’s storied restaurant. Which, as we all know, is just off Highway 29 in Yountville, Calif.

In a sense, one could even detect elements of wackadoodle California Republic optimism in an exceptionally exuberant JW Anderson collection. It was presented to critics as a boxed set of fabric samples and photos with the addition of pressed dried flowers, a paper mask of what looked like some rumbustious skate rat and little orange cards printed with New Age dithers: “Never Compromise,” “The Future is Unwritten,” “Keep Looking Up.”

There was something irrepressibly D.I.Y. about the collection, an effect that belied the masterful design and construction of patchwork coats slit high and flared like clown garments; oversize pockets ready made for boosting items from the department stores that no longer exist; and wallpaper prints and brocades that looked as if they were swiped from Joni Mitchell’s Laurel Canyon attic.

“A sentiment of youthful, freewheeling amusement composedly comes to the core,” read a line in Jonathan Anderson’s press notes. Even that utterance had an oddball SoCal cast to it, as though it had been cribbed from a Red Hot Chili Peppers lyric sheet.

If being sentenced to an indefinite term in Zoom jail has taught us anything, it is that in periods of prolonged exposure to tragedy we yearn for escape; often enough, that takes the form of silliness. What else are people doing trading bells for hula skirts and Froggie dresses on Animal Crossing New Horizons?

How else does one account for digital hordes of people picking up crochet hooks after a rainbow knit sweater from the JW Anderson spring men’s collection went viral on TikTok? Harry Styles wore it in rehearsal for a pre-lockdown performance on “Today.”

“I’ve never seen anything like it,” Mr. Anderson said. Because the nearly $1,500 hand-knit sweater is no longer available for sale, he posted the pattern online — an act of radical Etsy.

Even a gesture like his has roots you could trace, if you wished, to California groups like the utopian activists, the Diggers. Those early anticapitalists once staged semi-naked street theater happenings in the San Francisco of the 1960s, gave away food, and opened a bunch of Free Stores in Haight-Ashbury.

Is it a stretch to imagine that the stuff they offered gratis probably resembled Mr. Anderson’s irresistibly kooky granny sweater? I doubt it.

While Kim Jones’s show for Dior Men made reference to style gestures that likely originated on the West Coast (Teva-like sandals with socks, flap pocket shorts and berets worn Eldridge Cleaver-style), the collection for the most part paid homage to the tailoring traditions of the great couture house’s French founder.

For this outing Mr. Jones collaborated with Amoako Boafo, a Ghanaian artist he first met in Miami last year when a Dior men’s show was staged next door to the newly opened Rubell Museum, where Mr. Boafo was the resident artist.

In design terms, the connection is superficial to the point of indifference. Some of Mr. Boafo’s daubed portraits appear as prints. What is significant, though, is Mr. Boafo’s decision to forgo royalties from Dior in return for a donation to a cultural foundation the 36-year-old artist has set up in Accra, Ghana, just one element in an overdue cultural shift from appropriation to acknowledgment and homage.

The transformation, it is worth noting, is being spearheaded by Black artists like Mr. Boafo, Kehinde Wiley and Mickalene Thomas. In May, Mr. Boafo raised $190,000 from the online auction of his painting “Aurore Iradukunda,” with the proceeds going to the Museum of the African Diaspora, an institution whose goal is tracing the artistic and sociocultural threads of that forcible dispersion.

This singular museum stands not in New York or Paris or London, but right on gritty Mission Street in downtown San Francisco.