The question is, how representative are those people of the population at large?
Another question is whether people truly understand their privacy exposure? They know FB has some information on them because they submit it, but they don't know how much info in total (sites visited, location tracking, etc), how that data is combined/used, who has access to it, etc.
And, they assume that whatever FB is doing with their data must be OK/legal because laws.
I think that's what we saw with reactions to these recent revelations. When an inkling of the real privacy exposure surfaced, people freaked.
Of course they do. What sort of person is going to tick the "I don't care about privacy" box? I guess the same kind of person that ticks the "I'm OK with mass extinction" box. Those opinions are not very relevant in the real world.
I do think people are communicating via other mediums more than before though. It's anecdotal but most of my family and friends just gravitate towards iMessage , Facetime and Telegram to communicate by default now.
Could it be that people don't care about this issue because they care about Facebook anymore? There are alternatives now, people will just use them more and more over time.