Earlier quoted context omitted.
Deleting one's account does appear to be a mitigation
These constant articles are like watching someone stick their hand on a hot stove and complain over and over that it hurts. But try suggesting they take their hand off the burner and nope, freak outs and/or insults. It really is an option. It really is the best option. It isn't flippant or sarcasm.
Facebook has done a sufficiently good job of intertwining itself into people's lives, so that to abandon it would mean losing touch with family and friends, missing out on invitations to events, excluding one's self from valued discussion groups and more.
What people resent is that Facebook seems to hold people to ransom like this, now they've made people so reliant on it.
So, sure, people can just leave, fine. But don't diminish the fact that for many people, quitting Facebook would have serious drawbacks.