In any case, he is right. Look at the pattern, any large social network has these issues, which more or less seems like is related to how people interact. Twitter is massively toxic, Reddit is. Back in day Tumblr which was not current social media huge also used to have content Facebook gets blamed for.
Give a platform for people to publish and share and every opinion has the chance to be there.
It also doesn't have to be a massive broadcast platform, messaging platforms with small communities in the form of groups have these issues on a smaller scale. Though broadcast does make it worse.