This chart has been floating around, and I find it interesting to speculate about the reason for this shift.
Have attitudes changed this much? Do teens have less independence or fewer places to go to do these things? Are parents more involved in teens’ lives? Was vaping excluded in the study?
There are probably lots and lots of factors.
education about how using substances underage can mess up your brain development
ban on cigarette ads made them seem less cool
new laws that require id for anyone who looks 25 or under, and stronger enforcement of those laws
mobile devices are able to stimulate you at all times when you otherwise would’ve used a substance
more empathetic parenting makes kids listen to parents more
etc etc etc