“..because they take resources and knowledge to manufacture, and are physical objects that can be tracked. Taking these away by law works.”

Sorry but it doesn’t even work for physical objects. Guns are completely illegal in some cities (NYC, SF and Chicago, unless you have connections), so I suppose there’s no gun crime there, right? Or, research compliance rates when states have retroactively made certain firearms illegal and asked for citizens to turn them in or face the risk of criminal charges.

The War on Drugs has also been highly ineffective at preventing motivated individuals from obtaining certain physical objects.