I have to speculate that the reason why "social media is indeed corrosive to trust in governments, news media, and people and institutions in general" is oftentimes because it highlights their apparent failings (biases, lies, etc). That is, the problem is not primarily one of people failing to trust in trustworthy institutions, but due to a hyper-focus (retweeting) on the failings of those institutions.
As we communicate more, we find we don't agree as much as we thought we did, and that is divisive. Social media allows us to highlight and amplify the information about our disagreements.
As we communicate more, we find we don't agree as much as we thought we did, and that is divisive. Social media allows us to highlight and amplify the information about our disagreements.