I would think prohibition explained enough of how a population of people will not be government regulated on what we can , or can't do when it comes to our bodies. This is a freedom of choice .
Yes finances, druggies at work, financial downside are all factors. But no gangs, killings , and huge amounts of money saved back into the government would happen.
Whether meds are used for good or not is up to the individual, not the public.
Hasn't tobacco and alcohol caused less damage over the years than illegal drug murders?