democracy. the company's leadership knows how to make facebook and instagram safer, but won't make the necessary changes because they have put their profits before people. >> reporter: she alleged that the company's research showed that its platforms can be toxic for children and society at large. but the company failed to take action. the ceo mark zuckerberger push back. antisocial media was a through line for the entire year. bringing us to the number one media story of 2021. the vaccine disinformation divide. reliable info about covid-19 vaccines helped people get vaccinated and protected. but anti-vax lies and distortions went viral, from facebook to fox, in ways that worsened the pandemic's terrible toll. they took conspiracy theories from the fringes and moved them