The best way I've heard MDMA therapy being described is this - you have a large group of extremely painful neurons/memories, and going there is shocking and horrific to the point that you begin to grow a big moat of fearful neurons/emotions next to anything that connects with them. The point of therapy in general is to 1. Break down that fear moat (which frequently grows to be more painful than the underlying issue), and 2. Start drawing those painful neurons and memories out, but in as positive and understanding an environment as possible. At that point the memories/neurons get re-stored, still painful but with the added context of the environment they were last accessed.
MDMA takes step 2 and adds the most positive neurological/chemical setting possible for you to pull those painful neurons and memories out, and puts them in what can be described as a comforting blanket. It can absolutely quicken the process and help you eventually neutralize the traumatic and painful bundle of memories. Calling it a quick fix is such a misnomer - it is incredibly hard work to heal one's self from the inside, no matter the external helpers.
I imagine it could help, and probably be better than therapy alone, but lessoning of the negative feelings around painful memories can be treated with opiates too (which are far more addictive than MDMA, despite MDMA being far more euphoric). The problem is PTSD, anxiety disorders and personality disorders are incredibly intractable with the tools we have - if a therapeutic session could have 10x efficacy and safely get someone to a healthier state in 1 year rather than 10, it should absolutely be looked into.
Spiritual health is literally the most important need of any intelligent human, and yet it's incredibly hard to achieve in our current culture. We're a nation of drugged out, traumatized zombies starving for answers, and the loudest voices belong to snakes and idiots. It's an absolute disaster.
The first baby step of a solution is allowing and encouraging people to discover and to speak plainly about what is Good, what is Beauty, what are our obligations to ourselves and others, and why.
But everyone's brains are fried. They've simply accepted the ambient dull-minded morality seeped into our cultural fabric by a host of unmoral forces (and a few immoral), and the process of spiritual development for many has become a weakly cathartic but useless raging at the failure of their community to succeed within this framework. Then they're told: when this exhausts you, reach for the pill bottle.
It's incredibly sad.
Tell that to someone who is starving.
Hierarchy of needs: https://en.wikipedia.org/wiki/Maslow%27s_hierarchy_of_needs
Indeed, this illustrates quite well that physiological needs are the most important needs - if they were't, then they couldn't serve as a tool to escalate the stakes of the protest.
If spiritual needs were more important, you would have spirit strikes instead of hunger strikes.
It is the content of their souls that allows them to do what they do and this recognition that makes their demonstration compelling.
By the way, spirit strikes are very much a thing, and they are far uglier than hunger strikes.
Psychedelic experience is often a trigger that allows the one going through it to quickly bypass some (but not all!) obstacles on their Path.
e.g. a single MDMA experience might allow the person going through it to be more forgiving (albeit temporarily!) than they would otherwise have been able to, seeing the value of such a perspective and increasing the likelihood that they will engage in the on-going work that you describe.
As with most experiences, its impact (and duration of) exist on a spectrum.
You may find the Good Friday experiment to be of interest: