Zuckerberg, who was testifying before the Senate's Commerce and Judiciary committees, answered, "Senator, we run ads."
Therein lies Facebook's problem, says former Apple marketing executive Guy Kawasaki.
"Anything that's based on advertising is susceptible to distortion, and so that's ... inherent in the advertising model," Kawasaki tells CNBC Make It.
Kawasaki — who worked in marketing at Apple from 1983 to 1987 and again from 1995 to 1997 — told CNBC Make It in March that if he were Zuckerberg, to restore faith in the company he would charge an inexpensive monthly subscription fee for using the site to create an advertising-free platform.
"[A]dvertising is based on eyeballs, and somebody has got to pay the bills, so there's that model, or we can go to a paid subscription. So pay $2 a month and you get no ads, and you can control exactly what's in your feed and it would be a different model," says Kawasaki, who is now an investor, speaker and author of "Wise Guy: Lessons from a Life."
Facebook has faced many issues recently, particularly its lack of preparedness in the face of crises: It lagged in taking down a video of the March Christchurch, New Zealand shooting; in 2018 it was revealed that Cambridge Analytica got access to data from 87 million user profiles; and in October Facebook had to take down and Instagram accounts created by Russian trolls to manipulate the November midterm elections, to name a few.
"You don't see white nationalist ads in Slack," he says, referring to the office chat platform. "Well, the reason why is because Slack isn't an advertising model, it is a enterprise software model. So maybe the solution is enterprise software."
When reached for comment, a representive for Facebook directed CNBC Make It to Zuckerberg's January op-ed in the The Wall Street Journal in January, in which he said he was committed to keeping the platform free.
"I believe everyone should have a voice and be able to connect. If we're committed to serving everyone, then we need a service that is affordable to everyone. The best way to do that is to offer services for free, which ads enable us to do," Zuckerberg wrote.
"It's important to get this right, because there are clear benefits to this business model. Billions of people get a free service to stay connected to those they care about and to express themselves. And small businesses—which create most of the jobs and economic growth around the world—get access to tools that help them thrive," Zuckerberg wrote.
Of course, Kawasaki understands that if Facebook were to charge a subscription fee, some users would flee.
"There'd be a massive drop off ... because they're going to be a lot of people just saying, 'I will not pay,'" Kawasaki says.
"That would be a terrific and difficult leap for anybody," he admits. "That is completely disruptive and I don't know how the shareholders will react...."
But says, Kawasaki, "I don't see any other way."
Zuckerberg, however, called for government oversight in an op-ed he wrote in The Washington Post.
"I believe we need a more active role for governments and regulators. By updating the rules for the Internet, we can preserve what's best about it — the freedom for people to express themselves and for entrepreneurs to build new things — while also protecting society from broader harms," Zuckerberg wrote.
In addition to changing to a subscription service, Kawasaki says resurrecting trust in Facebook will require a cultural shift.
"Perhaps it's an educational process — that frankly everybody should figure out that you just should not to believe everything you see on the Internet — and whether that's Facebook or Twitter or Instagram or Pinterest or Breitbart or Fox," Kawasaki says. "You can't believe everything on the Internet. You can't believe everything in YouTube."
"One might make the case that ...at some point...the problem won't be exacerbated because people say, 'Aha, I get it now. I'm less susceptible to being fooled and to being tricked because I'm more skeptical.'"
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