I wonder if there is correlation to the opioid crisis, where the "downsides" (if you want to call it that) of drug abuse are so visible to teenagers that they are staying away from it. Doing drugs when it's associated with being "cool"/interesting like rappers is one thing, but when you associate it to fentanyl zombies living in the streets it loses a lot of its glamour.
I was not able to find the regional breakdown so it's just a conjecture though.