tw25656993
I'm not clear on how to quantify "enormous". Many people don't use facebook and still manage to make appointments and lead fulfilling social lives.
That said, it is clear that for many people the "social cost" is larger than the "facebook evil cost", even for people demanding government intervention. I guess for those people, the cost for demanding politicians Do Something is even less.
From economics there is the concept of "revealed preference", your individual subjective preferences are revealed by the choices you make. In this case, we can observe that Facebook's subjectively bad qualities are enough to demand politicians Do Something, but not enough to suffer the inconveniences of using a different chat app, etc.
The sad irony is that these points of concern are also potential advantages for competing platforms (e.g., Signal), and by regulating them away, Facebook/Whatsapp become further entrenched.