If you're curious on how it can be therapeutic, I recommend checking out the work done by MAPS https://maps.org/our-research/

Quick summary. MDMA originally got popular for use by psychiatrists in the earlier 1900s because of its therapeutic potential. In the therapeutic doses you administer in clinical settings like this Aussie law probably allows, it makes your brain more "plastic" and able to retrain the mind's associations to help recover from traumas like PTSD. Specifically, treatments like these are only shown to be truly helpful when "trip-sitted" by a professional, and sometimes show remarkable, and lasting results after only a few sessions. MDMA does not inherently make you start dancing, but it can allow you to unearth repressed emotions and be able to process them.

Here is the conclusion from the abstract of a Nature paper from 2021:

>MDMA did not induce adverse events of abuse potential, suicidality or QT prolongation. These data indicate that, compared with manualized therapy with inactive placebo, MDMA-assisted therapy is highly efficacious in individuals with severe PTSD, and treatment is safe and well-tolerated, even in those with comorbidities. We conclude that MDMA-assisted therapy represents a potential breakthrough treatment that merits expedited clinical evaluation.

https://www.nature.com/articles/s41591-021-01336-3