The issue wasn't a aggregation of how "harmful" the drugs were, it was chemical toxicity (as said so yourself), and so you should marginalize any difference in psychological dependence.
With that said, while I was likely wrong in claiming that MDMA is substantially more dangerous to a healthy brain than weed, your counterclaim that "mdma is less chemically toxic to your brain than thc" is clearly incorrect as well.
With that said, while I was likely wrong in claiming that MDMA is substantially more dangerous to a healthy brain than weed, your counterclaim that "mdma is less chemically toxic to your brain than thc" is clearly incorrect as well.