Tom Stafford:

A lot happened in 2016. It would be easy to imagine that the entire reason for this change was the election of Donald Trump as president, and to stop looking for other causes, but something else also happened which I think we should at least consider, and that other thing says something important about how social media and human psychology interact.

In March 2016 Twitter completed their transition to the algorithmic feed, meaning that it was the default for all users to have their timeline populated by what Twitter thought they would want to see, rather than a chronological feed of posts from people they had decided to follow.