IMHO, this is a very sensitive topic, and I'm glad I don't have kids for this to be a worry for me.
Smartphones became a big thing when I was already in high school, and social media at the time still wasn't this aggressive, but my father did monitor my activity on the PC, mostly secretly, and it made me feel anxious. This violation of privacy damaged my already shit/barely existent relationship with him. It's also why I'm so paranoid of secretly being monitored. You have to already have a pretty good relationship with your parents for this not to potentially mess you up, at least in my experience.
What the solution to this is, I don't know. Better digital/tech education in schools and at home would be a good step in that direction, but strict ad and product regulations should also be implemented, which - unfortunately expectedly - is being fought against (at least in the USA, according to the article).
Not in detail, but it actually does:
While younger kids may be reasoned with, teenagers aren't as easy to handle as some say. Puberty is a hell of a drug.