I think it’s also in part due to easier access at an earlier age compared to alcohol and the rapid increase in quality. Weed is easy to grow, and even kids have been selling it to their friends in school for forever. But gone are the days of buying skunk weed off some dude you barely know. There’s 13 year olds out there today smoking stuff of a quality that the hippies could only dream of.
Plus, when it comes to drugs, as a late Millennial, I knew a lot more kids who became heroin addicts as teenagers than alcoholics - and they started their drug use years before showing up on this graph. During Bush’s presidency, heroin from Afghanistan became a lot more easily accessible on the east coast, and I used to say when I was a teenager that heroin was more popular with my generation because it was too awkward to go to the bar and see your friends’ parents day drinking.
I’m not sure how it all factors in but there’s evidence that teenagers are using weed less: https://coloradosun.com/2024/06/26/youth-marijuana-use-colorado-legalization/
