There's a common saying in economics: "supply creates its own demand." This is false, at least in the way most understand it. Entrepreneurs can offer a product to test consumer interest, often discovering a demand the public did not know could be served, but if the entrepreneur errs, his investment evaporates and his business tanks.
The drug market isn't really any different despite the scare stories we heard from D.A.R.E.
The infamous tests with lab rats that showed how addictive drugs were have been run again with better rat conditions, and when rats are not isolated, but instead in a rat social structure with rat toys and a góod rat habitat, they are far less susceptible to addiction. The same applies to humans. We have to do the work to build a supportive society as a safety net for our communities, and remove the stigma of substance use on its own.
We know many people who drink alcohol in moderation with no societal collapse, but there are some who, through trauma or genetics or any number of factors, succumb to alcoholism. We know prohibition was not a solution that helped anyone, though. The same applies to drugs.