I work in a grocery store in Europe and now that Prime is produced in Poland and it doesnt cost absurdly, I can say that mostly, if not only, kids are the ones drinking it.
Edit: I just got back to work and checked that my country's biggest chains only sell Prime Hydration, which is caffeine free.
Are you fucking kidding me? Christ. "not marketed for people under 18" my ass, they fucking know Logan's main audience are kids (idk about ksi but I suspect his is similar) and that kids are absolutely gonna drink their fucking caffeine nuke.
But if you're drinking one drink that is the equivalent of 3 coffees, then even if you don't chug it, you'll still drink it faster than you would typically drink 3 coffees in a row, right? So it's the equivalent of chugging them in terms of caffeine uptake regardless. Unless they're taking over an hour to drink one energy drink, which the typical 16 year old isn't likely to do, it's like they're tossing back 3 coffees all in one sitting, something I personally wouldn't recommend for a 16 year old.
For adolescents that's 100-175mg/day, equivalent to 1.5 Monster energy drinks, or a large iced coffee. Per studies, that's fine for a 12 year old but I wouldn't want my 12 year old drinking adult beverages with any regularity. I'd rather work on there sleep habits, etc.
Worth noting that higher caffeine take is associated with things like poor diet/etc, but not causally linked.
Yes I said its an opinion, I made no claim it was medical science. My opinion is that in many cases, a teenager consuming reasonable amounts of caffeine is not something to worry about. I base this off of the knowledge I have of caffeine as someone who isn't a doctor. If you want a doctor's opinion, you should go to a doctor instead of the internet.