> Very difficult to legalize and tax meth, which is what this guy mostly sold. It’s hugely addictive and harmful, and you can make it in a home lab.

Sell the hard stuff in apothecaries or specialized drug treatment centers at a price point competitive to street dealers and offer people a safe space to consume said drugs. That should at least get fatal overdoses and contamination issues under control, and the consumers are in a place where they can be reached out to by social services (housing assistance, mental health).