Look at the adverse effects of alcohol vs weed. Just because alcohol is legal doesn’t make it the better of the two.
Prohibition of alcohol came about largely because the lack of potable water throughout much of our history forced people to drink apple cider. The busybodies amongst us took it upon themselves to do something about all those layabouts that were in the bag by noon and needed a nap before supper. Women’s suffrage kinda sealed the deal.