I strongly agree with you. I keep saying “don’t put on the Internet anything that you can’t justify on a nationwide television interview”, social networks are for your public persona - but people think the stakes are low, until shit happens. When it happens, their sense of security flies out of the window, but the percentage of shit happening is small enough to give them a false sense of security.
I’ve been a woman on the internet for a looooong time (since 1994 AFAIR) and I never could let my guard entirely down. This way lies stalkers. All my social networks had at least one password change request by some script kid. I look at the way younger people use social media and I shudder. I can see at least ten ways of easily scamming them or take control of their data.