Most in-person social activity is good for your mental health. Studies show this includes church: https://www.npr.org/2019/11/05/776270553/hidden-brain-does-g...

Facebook is singled out because they are the largest practitioner of surveillance capitalism. The entire idea of “optimizing for engagement,” where Facebook has been a pioneer and the largest player, is increasingly being shown to be a primary driver of political polarization, anxiety, bigotry, and hate crimes.

Thus Facebook is the new Big Tobacco.