Social Media is a big chunk. I think the single biggest factor is simply that the speed of evolution, be it technological, societal, cultural...all of it is moving too fast for the human brain to handle. In the background our brains are screaming. It's easy to look at old people and see that most of them seem to bitch about kids these days, how society is crumbling, how it was much better back in their day, etc. That's a symptom. The human brain doesn't always deal well with change, much less rapid change.
Humanity took thousands and thousands of years to go from hunting and gathering to farming. The society norms and gender roles that guided us since the beginning of time starting being upended in the last half of the 20th century. And yet only in the last 200 years we've gone from a still mostly agrarian culture to the industrial revolution, high-tech industry, technological wonders...from a species that outside of migration was mostly unchanged in major ways from the last tens of thousands of years. Culturally, in only the last 100 year, we've had women's rights, repeal of segregation, gender fluidity, a downturn in religion, and the replacement of actual community to digital community.
Ignore the fact that old people are ill equipped to handle change. I don't think Humanity is prepared to handle this kind of repaid evolution...of literally everything around us...without our brains crying out in terror. Social Media is just the most obvious influencer.