He'd be absolutely correct—just as with alcohol and tobacco.
It's all based on this scary, threatening, annoying concept called "Liberty", wherein—if an individual isn't infringing on the rights of somebody else via force, fraud, or negligence—they have every right to be left the f-ck alone by government and nanny-staters, and to engage in the pursuit of happiness as they see fit...
“if an individual isn’t infringing on the rights of somebody else via force, fraud, or negligence”
Fatal accidents caused by drivers with marijuana in their blood have close to tripled since the State of Washington ‘legalized’ marijuana.