This is absolutely true on both counts. For as much as social media is decried for negative effects on mental health and IRL socialization, healthy lifestyle & fitness inspos are absolutely having an impact. The nice thing about this is that it translates in obvious ways to IRL lifestyle mods, which when they show positive effects (better sleep, better skin, improved fitness, etc) become self-reinforcing habits. Among other things, alcohol consumption is way lower in young people than older generations, and although other recreational drug use is still "a thing", overall knowledge about the effects & impacts of recreational drugs is far more pervasive than in the past (as a young Gen-Xer myself, the prevailing mentality in the late80s-early90s was "drugs make fun times more fun" and that was about it).

I expect lots of formal study of these phenomena in coming years. As a parent of kids 7, 13, and 16 who spends a fair bit of time around school campuses & youth sports teams, for all the whining and complaining adults do about young people, my experience is that today's youth are by far the most empathetic, compassionate and best adjusted yet. They're going to be ok (provided we can afford to educate them and then hire them into the working world).