YouTube cofounder Steve Chen is the latest tech trailblazer to warn against social media’s impact on kids. Chen warned in a recently published talk that short-form video “equates to shorter attention spans” and said he wouldn’t want his own kids to exclusively consume this type of content. Companies that distribute short-form video (which includes the company he cofounded, YouTube) should add safeguards for younger users, he added.A YouTube cofounder who helped pave the way for our modern, content-obsessed world is the latest tech whiz to come out against short-form videos because of their effects on kids. Steve Chen, who served as YouTube’s former chief technology officer before it was acquired by Google in 2006, railed against the TikTok-ification of online life in a talk earlier this month at Stanford Graduate School of Business.“I think TikTok is entertainment, but it’s purely entertainment,” Chen said during the talk, which was published on YouTube Friday. “It’s just for that moment. Just shorter-form content equates to shorter attention spans.”Chen, who has two children with wife, Jamie Chen, said he wouldn’t want his kids only consuming short-form content, and then not be able to watch something longer than 15 minutes. He said he knows of other parents who force their kids to watch longer videos without the eye-catching colors and gimmicks that hook especially younger users. This strategy works well, he claims.“If they don’t get exposure to the short-form content right away, then they’re still happy with that other type of content that they’re watching,” he said. Many companies have had to rush to offer short-form content after the rise of TikTok, he said, but these companies now have to balance their motivations for monetization and attracting users’ attention with content that’s “actually useful.” Companies that distribute short-form video, which includes his former company YouTube, could face problems with addictiveness. These companies should add safeguards for kids on short-form content, such as age restrictions for apps and limits on the amount of time some users can use them, he said. Chen joins fellow tech trailblazers Sam Altman of OpenAI and Elon Musk in sounding the alarm about social media’s impact on children. In a podcast interview last week, Altman specifically called out social media scrolling and the “dopamine hit” of short-form video for “probably messing with kids’ brain development in a super deep way.”Musk, who owns the social network X (née Twitter), said in 2023 he doesn’t have any restrictions on social-media use for his children, but added this “might have been a mistake,” and encouraged parents to take a more active role in their kids’ social-media habits.“I think, probably, I would limit social media a bit more than I have in the past and just take note of what they’re watching, because I think at this point they’re being programmed by some social media algorithms, which you may or may not agree with,” Musk said.This story was originally featured on Fortune.com