I do not, however, agree with their solution. Turning off the news/Facebook/Twitter and ignoring everything happening around you is not going to make things better.
The world has made a lot of progress over the last few centuries (as the article calls out), but all of it has been driven by common people like you and me getting outraged over things that might not directly concern us. Anger is sometimes justified.
Instead, when you read something that angers you, take a few minutes and do that extra step of research. Could it be completely fake? Does the headline reflect the contents of the article correctly (it is normally not written by the author)? Is the data researched and sourced? Is what you are reading heavily opinionated? Are you subscribed to a healthy mix of sources?
If enough people actually did this (instead of reading the title and going straight to Twitter/Reddit/HN), meaningless outrage will disappear without the trade-off of not being informed about the world. You will organically discover that everything is a lot more reasonable and moderate than people want you to believe. And if something actually isn't, you will be able to see it.