I think of MDMA as an amphetamine, A very very compelling one, I could go my whole life without any more dexedrine, but would have a real tough time giving up on MDMA completely.
It seems to give many people who take it an aesthetic to which they glorify, an indescribable moment of their time on earth that they so urgently grasp to explain but simply cannot...so they take more MDMA to get back to that place!
It's an incredibly "gimme" style drug, it is an amphetamine it is very addictive but at the same time can liberate one from a lifetime of bullcrap.
I think it's what some refer to as a catch 22. but in the realm of "magic pills" MDMA is one of the truest, fastest, most up-front mind altering substances known. It causes similar "magic" in every case.
similarly people can just have horrible times on it and trip to hard for what they're used to. but for drug users typically MDMA is a staple.