The Taliban has not once, but twice eradicated Afghanistan's poppy cultivation, the world's largest source of heroin. Despite western accusations, it has never been The Taliban behind the Afghan drug industry, but only ever the US and its allies, with billions in profits breezily laundered through the global financial system.
No matter which side you are in the statement “The Taliban’s successful opium ban is bad for Afghans and the world.” is objectively true. The shortfall in opioid production will easily be made up from other sources, likely adulterated with synthetics that cause more harm. As for the Afghan farmers who grew the stuff they've not been given another alternative..they just had their crops destroyed and have no other sources of income.