maybe it's the idea of stress. we learn too much about it: what it is, how to 'handle' it, how it negatively affects us, etc.
during my parents' school days, they hadn't even heard of stress and had absolutely no idea what it was and I expect a lot of older people will agree that when they were at school, it wasn't so well-defined.
then, on top of that, they throw out new specifications without any warning and make exams 'harder' because 'too many people were getting A*s' and that's just not cool. like, nobody wants harder exams. they're stupid when almost everyone will do badly on them.
let's not even talk about social media. it's just ridiculous. we have stuff like studyblrs, studygrams, studytubers and so much more and it looks like they're all so organised and getting their life together and because we just naturally compare ourselves to them, we feel inferior and that, I think, just puts on so much pressure on us. I'm saying this because I used to run a studygram, albeit a small one, and seeing everyone be organised was just too much for me. I didn't feel the same and it just negatively affected the way I perceived myself. And that's just on a studying scale.
So yes, to put it shortly, I believe we are more stressed than previous generations. There's lots of reasons behind it but I've mentioned a few and I believe there are more.