Democracy is being eroded by an overwhelming information ecosystem buoyed by major tech platforms, former President Barack Obama said Thursday.

Why it matters: Obama's comments reflect a shift in his feelings toward technology, in contrast to his embrace of Silicon Valley and social media as a force for good as president.

Driving the news: Obama made the remarks at an event about disinformation and democracy at Stanford University, co-hosted by the Obama Foundation.

What they're saying: People are overwhelmed by the information served up by social media companies, and it contributes to division and confusion over what can be trusted, he said: "If we do nothing, I'm convinced the trends we're seeing will get worse."

• Obama said it's time for the government to step in: "Just like every industry with an impact on our society...these platforms need to be subject to some oversight."
• Misinformation is killing people, he said, pointing to distrust over the COVID-19 vaccine and the deadly Jan. 6 Capitol insurrection. Companies are trying to do better, but they're still not doing enough, he said: "These companies need to have a North Star other than profits and market share."

The intrigue: Obama said he should’ve known the extent of the problem sooner, citing the 2016 election as a major moment in the outset of misinformation on social media.

• "What does still nag at me... was my failure to fully appreciate at the time, just how susceptible we had become to lies and conspiracy theories, despite spending years being a target of disinformation myself," he said.

Details: Obama suggested more transparency from platforms, some reform to the Section 230 law that largely keeps tech companies liable from what other people post, and boosting revenues for local news organizations.

• He called social media of today "grim," and said the U.S. should be at the forefront of conversations about online content moderation, but Europe has taken the lead.

The bottom line: Social media did not create society's problems, he said, but has inflamed and exacerbated them.