This has been up a while and has a lot of comments, and there is no mention of Cambridge Analytica? A lot of people talk about polarization on Facebook around 2016... that was the intended result of deliberate and concerted efforts. Whether or not user metadata disclosure was done intentionally, the data was then used to radicalize target populations on certain political issues https://en.wikipedia.org/wiki/Facebook%E2%80%93Cambridge_Ana...
Of course people are leaving and don't trust them.