Actually, they added a methyl group to MDA. MDMA is also less potent by weight than both MDA and methamphetamine and clinically safer than both.
As far as abuse potential, it’s basically very shitty speed when you try to take it to often. The primary mechanism of action is way different than methamphetamine. Which makes it very hard to redose and get high again. This means it has a difficult time forming the dopamine reward cycle we see with cocaine and methamphetamine.
It’s also never smoked and rarely shot, which are the two routes of administration that most easily set up dopamine reward pathways because the drug kicks in so much faster than via ingestion.
Which isn’t to say people won’t try to abuse it. But that has way more to do with the person’s personality type than the drug, as MDMA really doesn’t have the same abuse potential as it’s parent compound (MDA) or it’s relative (methamphetamine).
In my experience, MDMA is less addictive than sex or video games and isn’t on the same level as methamphetamine at all (and I’ve shot both).
Source: I’m a drug nerd who has taken some college level pharmacology focused on illegal drugs. I’m also a recovering meth addict who got over my meth addiction when some friends gave me molly twenty something years ago.