The author contrasts contemporary street meth, which is reportedly created in vast quantities using a variety of toxic industrial chemicals, to illicitly produced meth from 15+ years ago, which was primarily made from naturally-occurring ephedrine.

The point of the article, I believe, is to outline how synthetic production has changed the end product and the way it affects the user. It is said that psychosis observed in users of the early 2000's type of ephedrine-sourced meth was typically due to the user being awake for several days, where as modernly produced meth can induce such psychosis within hours of use. This seems to indicate higher neurotoxicity, and the author questions whether it is due increased potency or contamination of product through production.

Adderall is a mixture of amphetamine isomers. Which is prescribed all the time. (And let’s be honest, abused…)

Methamphetamine is not Adderall. Meth is almost never prescribed, as it has far higher neurotoxicity, and far higher binding to serotonergic neurons.