Wow, this is such a thoughtful post. I really drummed my fingers thinking of something witty to reply.
About #1: From my childhood experience, this is accurate. Youth fashion magazines and network TV from 7PM to 10PM played and outsized role to influence our (small) world view. However, I find it interesting that as social media has exploded, there is parellel movement to reduce digital post processing on models photographs. It is still a moving target, but the trend is less and less processing of photographs in fashion magazines and adverts. (Note: This "commitment" varies wildly by region!)
About #2: This comment is so deep. I remember reading the novel "Orphan Train" a few years ago, and the author spent considerable time pulling you into the world within which these young people lived. Granted, the events occur about 100 years ago, but they help us the understand the pressures of youth from four generations ago. By the end, you felt like a movie director, peering into their fractured lives. Generally speaking, I think about a "generation" as being 25 years. If we look back 100 years, someone born in 1921, then each 25 years is a new generation. Assuming these people lived in relatively free and prosperous places... I dunno, pick Belgium or Argentina or Australia... each 25 years, children's lives would be hugely different than their parents due to major social advances, improved education, and new media outlets. In my generation, one of the biggest concerns was "peer pressure" and "too much TV or video games". Some of that still exists, but it has morphed more towards bullying (including early-age homophobia and transphobia) and too much Internet / social media. An exciting question: What comes after this generation? Too much AR / VR!?