A lot of it is being stuck in a cycle.
Psychoactives are psychoactive because they break the pattern recognition our brains are constantly doing in the background, it's why faces look so fucking weird when you're on them.
The human brain wants symmetry, so when we see an asymmetrical face our brain "fixes" it. The more symmetrical the face, the less "work" it takes, which is why people find symmetrical faces pleasing to look at.
Our brains are just lazy.
So you fuck up that pattern recognition and "autopilot" and it's essentially resetting your brain by turning those processors off and waiting for them to come back online
This isn't new or groundbreaking, science has known it for a long time even with governments heavily limiting the amount of studies. It's just really really fucking hard to get street drugs approved for medical treatment when no pharmaceutical company holds the patent.
They're all going to lobby against it and push for ones they tweaked enough to patent, even if they're less effective.