Why did you take this as an invitation to do a purely theoretical exercise in listing possible mechanisms for neurotoxicity? At the very least you ought to have anchored your reasoning in actual risky MDMA use, what people actually do, instead of just ranting out words that could scare a layperson. I.e. behaviours that are common, like combining MDMA with alcohol, or dopaminergic psychedelics like LSD and 2C-B, or forgetting to drink water, or whatever that isn't pseudo-academic stuff like 'sped up redox cycling of dopamine quinones'.
I also think you should have taken the time to show that you have an understanding of why millions of people disagree with you. In my opinion it would also be prudent to compare the risks you see with other neuronal risks, like living in an environment with ICE exhausts or having kids and suffering sleep deprivation for years on end or just plain old poverty. The latter is shown to, on average, have detrimental effects on the brain that can be clearly visible in medical examinations, unlike sporadic, responsible use of MDMA.