Fake MDMA is such a common thing, it really would benefit from being legalized from a harm reduction standpoint
MDMA content in the pills is often overstated, but still high (even too high, referring to the health organization guidelines); this is IMO the most damaging effect of lack of regulation - it's impossible to know how much MDMA one is going to ingest.
I agree 100% that MDMA legalization is a benefit. As first step though, drug checking centers are a huge (and realistic) step forward.