Many do not text or email, they use Facebook's messaging system. They would not even have the information required to connect elsewhere. There is also a huge

Many do not text or email, they use Facebook's messaging system. They would not even have the information required to connect elsewhere. There is also a huge difference between people making the decision to stop using social networking, and being suddenly and unexpectedly cut off from a support network. The former can have positive effects on mental health, the latter will certainly not. I say this as somebody who deleted their Facebook account over a decade ago.