I think that young people today don't perceive themselves as having any free time, and so they treat new things as they're taught in school: optimize the solution, get your grade/get paid, and go back to the precious little free time you have available to enjoy your life.
The disappearing free time is partially true, as the reach of the school environment grows and homework/extracurricular burdens increase. It's also partially imagined, because most young people burn 4-9 hours per day on their phones. It's not their fault, since phones are designed to be addicting for young people specifically. However, the end result is that the class of people who should be the most restless, virile, excited, and driven in society--kids age 12-20--is the most over-scheduled and exhausted.
If you took a modern young person and stuck them on a reservation where the level of technology and pace of life matched the '80s and '90s, they'd start behaving like young people again.