Unsubstantiated claim.
Actually, around my area in WA, the prevailing observation is that those who already use are continuing to use, those who don't aren't, and a few old fogies are getting back into it. The shop is seeing next to no customers who have never used before.
You left out younger kids who will now use because of availability, and “acceptability” with a law that legalizes it. Unsubstantiated, yes, but we will see...