As a member of the "younger generation," I'm familiar with pretty much every social media platform. I grew up with them. And the nice thing about most forms of social media (I'm thinking especially of Facebook here) is that you have complete control over who's seeing those posts and pictures and details about your personal life. If you don't want the world to see pictures of your kids, limit those photo albums to family members only. Etc. The problem is that a lot of people don't understand how this works, either because they haven't been trained or haven't bothered to look at the instructions, so they end up posting private details of their lives to the entire world. There's a website called Openbook where you can search through public status updates from profiles that people have (probably unintentionally) left totally exposed.
On the other hand, even people who know how to limit what they share to the people they want to see it can share too much. We all know people who seem to spend all their time online complaining about their boss, or sharing details of embarrassing illnesses, or publicly arguing with a spouse or family member. It can be very uncomfortable even if they aren't sharing that info by accident. Some people "overshare," I guess; but often times that's no different from the way they behave in real life. The nice thing is that in real life when someone starts giving you "TMI" you usually have to nod and smile until they go away, whereas online you can ignore them!