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The worst technology of 2021

Face filters, billionaires in space, and home-buying algorithms that overpay all made our annual list of technology gone wrong.

December 29, 2021
2021 tech fails concept
Mel Haasch

We’ve never relied more on technology to solve our problems than we do now. Sometimes it works. Vaccines against covid-19 have cut the death toll. We’ve got virus tests and drugs, too.

But this isn’t the story about what worked in 2021. This is MIT Technology Review’s annual list of cases where innovation went wrong. From the metaverse to Alzheimer’s drugs, the technologies on this are the ones that didn’t work (or that worked too well), the Eurekas we wish no one had ever had, the inventions spawned by the dark side of the human intellect. Read on.

Biogen's Alzheimer's drug

The best kind of medicine is inexpensive, safe, and effective. Think of setting a bone in a cast, filling a cavity, or administering a $2 polio vaccine. The worst medicine of 2021 is exactly the opposite. It’s Aduhelm—an Alzheimer’s drug that went on sale in June in the US at a yearly cost of around $56,400, without much evidence it helps patients, but with substantial risk of serious brain swelling.

The drug, sold by Biogen, is an antibody that attaches to brain plaques. Aduhelm flopped in a large human trial, which showed no concrete benefit to patients with the brain disease. Yet the company and the US Food and Drug Administration decided to move forward in June, over the objections of the agency’s expert advisors. Several resigned. One, Aaron Kesselheim, called the episode “probably the worst drug approval decision in recent US history.”

Yes, we need new treatments for Alzheimer’s. But this approval marked a concerning trend toward approving drugs using a weaker type of evidence known as “surrogate markers.” Because Aduhelm causes a measurable reduction in brain plaques—a marker of dementia—the FDA concluded there was “reasonable likelihood” it would benefit patients. One problem with such guesswork is that no one knows whether these plaques cause disease or are just among its symptoms.

Aduhelm, the first new Alzheimer’s drug in 20 years, is already a fiasco. Few patients are getting it, Biogen’s sales are minuscule, and at least one person has died from brain swelling. Since the approval, the company has cut the drug’s price in half, and its research chief has abruptly resigned.

Read more:How an Unproven Alzheimer’s Drug Got Approved,” New York Times .

Zillow’s house-buying algorithm

“Don’t get high on your own supply” is a familiar business maxim. The real estate listing company Zillow did exactly that, with catastrophic results.

The company’s real-estate listing site is popular, and so are its computer-generated house values, known as “Zestimates.” The company’s error was using its estimates to purchase homes itself, sight unseen, in order to flip them and collect transaction fees. Zillow soon learned that its algorithm didn’t correctly forecast changes in housing prices. And that wasn’t the only problem.

Zillow was competing with other digital bidders, known as “iBuyers.” So it did what any house hunter determined to make a deal would do: it overpaid. By this year, Zillow was listing hundreds of homes for less than its own purchase price. In November, the company shuttered its iBuying unit Zillow Offers, cut 2,000 jobs, and took a $500 million write-off in what the Wall Street Journal termed “one of the sharpest recent American corporate retreats.”

Zillow will stick to its original business of selling advertisements to real estate brokers. Its Zestimates still have a home on the site.

Read more: What Went Wrong with Zillow? A Real-Estate Algorithm Derailed Its Big Bet,” Wall Street Journal


Ransomware is malicious software that kidnaps a company’s computer files by encrypting them. Criminals then demand money to restore access. It’s a booming business. Ransomware hit a new record in 2021 with more than 500 million attacks, according to cybersecurity company SonicWall.

The problem came to wider attention on May 7, 2021, when a ransomware group called DarkSide locked the files of Colonial Pipeline, which operates 5,500 miles of gasoline and fuel pipes stretching between Houston and New York. The company quickly paid more than $4 million in Bitcoin, but the disruption still caused temporary chaos at gas stations on the US East Coast.

By attacking critical infrastructure, the gang drew more attention than it expected. The FBI tracked and seized back about half the Bitcoin ransom, and DarkSide later announced on its website that it was going out of business.

As long as people pay ransoms, however, the criminals will be back.

Listen to more: The Extortion Economy, a five-part podcast series on ransomware by MIT Technology Review and ProPublica

Space tourism

If you’ve ever been to the Louvre in Paris, you’ve seen the crowds of wealthy tourists waving iPhones at the Mona Lisa, even if they can barely see it. The famous painting is now just a bucket-list item. Get there, snap a selfie, and then on to the next “experience.”

Now a snapshot floating above planet Earth is what’s on the wish list for a few billionaires and their buddies. It’s called “space tourism,” but we wonder what the point is. Wikipedia defines it as “human space travel for recreational purposes.”

It’s not exactly new: the first paying customer launched in 1984 on the space shuttle. But this year the trend expanded in clouds of burnt fuel as Virgin Galactic founder Richard Branson and then Jeff Bezos, the founder of Amazon, each rode vehicles up to the edges of space.

It’s all about an exclusive experience. But, likes lots of favorite tourist spots, it could soon get crowded up there.

Blue Origin, the space company started by Bezos, plans an “orbital reef,” a kind of office park circling the planet where people rent space to make films. On Virgin’s website, Branson says the reason for his space plane—with rides costing $200,000 and up—is to get “millions of kids all over the world” excited about “the possibility of them going to space one day.” Get your selfie sticks ready.

Read more:Space Tourism Is a Waste,” Gizmodo

Beauty filters

This year, Facebook rebranded itself as “Meta,” signaling Mark Zuckerberg’s bet on the emerging virtual worlds of work and play. The appeal of digital reality is that you can be anyone and do anything.

But early experience with one form of augmented reality at scale shows that different isn’t always better. We’re talking about beauty filters—apps that let people, often young girls, smooth their skin, thin their noses, and enlarge their eyes in digital images. These apps are not just gimmicks, like those that give you bunny ears. For some young women, they enforce false images they can’t live up to. The message kids are getting is not “Be yourself.”

Beauty apps are available on Snapchat, TikTok, and Meta’s Instagram—and millions are using them. Meta has already barred some apps that encourage extreme weight loss or plastic surgery, acknowledging some problems. But this year a whistleblower, Frances Haugen, stepped forward to say that Zuckerberg’s company had further data showing that addictive use of Instagram—constantly posting images, seeking likes, and making comparisons—“harms children” and creates “a toxic environment for teens.”

People feel bad when they use it, but they can’t stop. Beauty filters that make people look good but feel unhappy are a troubling start for the metaverse.

Read more: “Beauty filters are changing the way young girls see themselves,” MIT Technology Review

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