Public social networks are poison, they’re inimical to privacy, and we need to get off of any that harvest personal information. Telling people to “quit FB (and other similar services)” may come off wrong, but for a long time so did “quit smoking.” I get it, I’d love to have cigarettes that are healthy and delicious, but until then... quit smoking. Maybe someday public social media will be safe and sane, but until then... quit.
I don't think it's an unhelpful answer to a complex problem. I think it's the right answer.
"Only" oversells the option. There's also:
* mix fake/mining-hostile data in with real data as needed for social media profiles * use public institutions to enact consumer protection policies
Both of these have their own difficulties and limits, of course, but so does ditching social media entirely.
Phone numbers change. This is less frequent now that we have mobile numbers, but they still change. Email addresses can also change as people move through different phases of life. Hell, email seems to be becoming unreliable as calling since unsubscribing from mailing lists you never joined doesn't seem to work any more.
I get it. Facebook is evil.