I don't think you can blame MDMA for drinking 10L of water. I think that's entirely a socialized overreaction to the typical side effect of MDMA (not noticing you're overheating from constant activity in a crowded space).

MDMA doesn't give you the level of thirst for water that you're describing. It does generally make you feel warmer than usual, but there are plenty of ways to cool down other than drinking water (drinking water helps, but going outside works too). Also, it doesn't have the same effect as alcohol on your sense of judgement, you can do stupid stuff on it but generally you're more aware of what's going on.

That's not to say it's for everybody (people with heart defects probably shouldn't mess with it, and IIRC it can deplete serotonin in the long run if overused), but the main risks appear to come from those who take large doses and/or mix it with other drugs (through their own fault or by a dealer cutting it with something else).

Drugs can't bear fault. They have no means of moral expression. The person who took the drug bears all culpability.