It's not that easy :) The "take daily for life" pills work always; you can have the crappiest day of life and take a pill and you're happy. That's why they're addictive, even stuff like cigarettes or alcohol -- always work, always calm you down, bad trip impossible.
Psychedelics require preparation, and active cooperation on the patients side. If you think you can be depressed and suicidal and eat a mushroom and have it all gone you are in for a world of bad trip, that will have consequences after the bad trip: insanity, panic attacks, anxiety, and symptoms of PTSD. Basically, psychedelics aren't an immediate fix, they require preparation before and taking actions after the trip.
Psychonautics requires learning; experienced and knowledgeable people can guide their mind to benefit greatly from a bad trip, but most people are not be able to handle it, and delve even deeper into depression or whatever. Some killed themselves afterwards or during. Some have peed their pants while crying and shaking throughout the trip but came out better. Some had absolutely wonderful experiences with psychedelics.
From personal experience, your set and setting will determine whether you discover the wonders of the universe or hallucinate a penis staring at your face, thinking you are being raped for 8 hours. I am not joking.
People like immediate fixes, hence why psychedelic therapy doesn't get much attention.