It’s a reasonable question, a Los Angeles jury just decided. In a closely watched landmark case, the court found in favor of a 20-year-old plaintiff known as KGM, who sued Meta and Google, alleging that design features like infinite scroll, filters, and autoplay on Instagram, Facebook, and YouTube kept her online as much as 16 hours a day and helped fuel her depression, anxiety, body dysmorphia, and self-harm. (TikTok and Snap settled in the same case earlier this year.) The verdict could open the door to thousands of similar lawsuits—and even end up limiting how far Big Tech can go in competing for our attention.

The legal challenges, alongside a growing body of brain research and concerns raised by health organizations, are adding urgency to a question much discussed in academia and over dinner tables: Is “tech addiction” real? And if so, what does that mean for the business model that powers the world’s most valuable companies?

The answer is not simple. At one end of the spectrum is the kind of “addiction” most of us joke about: checking email before we’re out of bed; scrolling TikTok in the checkout line; refreshing Instagram when we’re bored. At the other end is a far smaller group: people like the plaintiff in the lawsuit and Sarah Hill, a young woman Fortune met at a residential treatment center for digital overuse outside of Seattle. Hill’s compulsive use of an AI chatbot app, Character AI, became so all-consuming she flunked out of college and ended up at reSTART, one of only a few such centers, in the U.S. or elsewhere.

There, clients give up smartphones, gaming, social media, and other tech—often for months—and spend 24 to 30 hours a week in intensive therapy. The treatment costs, on average, around $1,000 a day, though sometimes it can be covered by insurance for associated disorders such as depression and anxiety.

It’s worth it, Hill says. “After making so many mistakes, I’m finally putting a foot down and saying, ‘I want to get out of this endless cycle,’” she tells Fortune. “I need to do something to better myself and my life.’”

reSTART cofounder Cosette Rae has been treating clients for nearly two decades—gamers who won’t leave their homes; adults glued to virtual reality or pornography; and, increasingly, people hooked on AI chatbots. Tech, she says, is “everywhere,” which means people in recovery are constantly forced to say no to something they can never fully avoid.

The stakes are only getting higher, Rae says, in the AI era. She worries that increasingly sophisticated chatbots and virtual companions could become “substitute attachment figures” for young people, displacing real relationships. She fears a looming “tsunami” for families who don’t yet grasp what their kids are up against—or how these products might reshape their future.

Stanford psychiatrist Anna Lembke, author of Dopamine Nation and an expert witness called by the plaintiffs in the Meta and YouTube trial, argues that compulsive tech use taps into the brain’s reward circuitry in ways that mirror drug addiction. When people refresh social media feeds or win a round of a video game, their brains get dopamine jolts that train them to seek that hit again and again. Over time, those bursts can desensitize reward pathways and weaken the prefrontal cortex—the part of the brain responsible for planning and self-control—making it harder to resist urges even when work, school, or relationships are suffering. Brain imaging studies of people diagnosed with internet gaming or social media disorders have shown structural and functional changes in these regions that resemble what doctors see in gambling and other behavioral addictions.

The science is far from settled, and tech companies are quick to point out that tech addiction is not formally recognized in the Diagnostic and Statistical Manual of Mental Disorders; the DSM only flags “internet gaming disorder” as a condition that merits more study. Some researchers argue that slapping the “addiction” label on heavy tech use can actually backfire. In one set of surveys, California Institute of Technology researcher Ian Anderson and Wendy Wood, a professor at the University of Southern California, found that when people described their Instagram use as an addiction, “they felt stuck, less confident that they had the ability to change.” Yes, they wrote, companies should “amend their platforms to help users regain control over their habits.” But they concluded, “The truth is: Heavy use is not necessarily an addiction.”

In the KGM case, Instagram head Adam Mosseri told the court that social media is not “clinically addictive.” “We respectfully disagree with the verdict and are evaluating our legal options,” a Meta spokesperson said when reached for comment Wednesday. 

A spokesperson for YouTube parent company Google said the company also disagrees with the verdict and plans to appeal. “This case misunderstands YouTube, which is a responsibly built streaming platform, not a social media site,” the spokesperson said. (TikTok declined to comment, and Snap did not respond to requests for comment.)

What, if anything, should be done? Policymakers are floating answers, from state-level warning labels and restrictions on personalized feeds for minors to outright bans on teen social media in some countries. Platforms have rolled out an array of opt-in safeguards, teen modes, and screen-time nudges. 

But as tech investor and author Nir Eyal points out, asking companies to make their products less appealing and engaging can be a tough sell. He sees some of the concern about tech addiction as a “moral panic,” and argues that it’s unreasonable to make tech companies responsible for some people’s immoderate use of their products. “Stop making the product interesting? That’s dumb,” he says. “That’s why we use the product. That’s called ‘entertaining and engaging.’” He argues that the focus should be on making products “better and safer,” not less fun to use.

Read Fortune’s magazine feature on tech addiction here.

This post has been updated with comments from Google and Meta following the verdict.