Well, O.K.: Data might not be sold. But it is used. And luxury has benefited.

When Ms. Oluwole opened her division four years ago, she said, she faced resistance from the old-school fashion names, long averse to digital novelty. Slowly, she earned executives’ trust — not only because she is a savvy marketer with a master’s degree in business administration from Columbia University, but also because she is a devoted luxury consumer. On the day of the interview, she had augmented her swishy navy Maje minidress with Chanel boots that had a golf-ball-size pearl suspended in each clear Lucite heel, a stainless-steel Rolex Datejust watch and a Louis Vuitton ring adorned with the initial M.

Her iPhone was enveloped by a Goyard case. Her business card holder: Chanel. This season, she attended the Christian Dior and Berluti shows. “Luxury is what I do,” she said, “but it’s also part of my innate life.”

Born in Lagos, Nigeria, to a family of doctors and lawyers, and educated in England, Ms. Oluwole joined Facebook in 2006, when she was a pre-med undergrad at Stanford University and the start-up was still an inter-university network with just 150 employees. In 2013, she saw the potential of the fashion world, and persuaded her then-boss Carolyn Everson, Facebook’s vice president of global marketing solutions, to establish a department focused squarely on the luxury sector.

In 2015, Ms. Oluwole opened her two-person “global luxury hub” in Paris. She rented a small apartment in the hipster neighborhood of Montorgueil (and has since bought a home in the tony 16th Arrondissement) and enrolled in French classes at the Alliance Française.

About the same time, Instagram hired Eva Chen , the well-connected former editor in chief of Lucky magazine, as director of fashion partnerships for the platform in New York. Ms. Chen’s brief has been to consult with fashionable figures, such as models, designers, stylists and celebrities, and help them create posts that increase their followers (her services are free).