I haven't read the linked paper, but if it's conclusion is correct and students are spending less time studying, then all I can say is "good for them"!

Honestly, it seems like kids are expected to work flat out in school these days, killing themselves to get top grades and doing as much extra curricular stuff as they can schedule. It's as if taking a larger course load and burning out is a badge of honour.

If I went back to school now I would take a light course load in order to better spend my time on my own projects. I wouldn't worry too much about my grades as long as they were "good enough" and I would just try to enjoy myself and keep it fun.