IMHO it has to do with your ability to deal with anxiety, fear, and the extreme emotional/mental states that can arise with the use of psychedelics. Same thing happens in situations in real life, and people deal with them differently. Nothing to do with the drug, dose, or experience, but rather the individual.
DMT/LSD/whatever is just a catalyst. An unpredictable one at that. People unprepared to face their fears, deal with anxiety all those things that exist in normal life, might have trouble with psychs. But then again theres the people who have conquered those everyday life obstacles by intense psychedelic hell rides, through insights on how their emotions affect them and their mental health.
For me, it was realizing that fear, anxiety, all the stuff we tend to regard as bad, is not really that. Its just a part of the whole, a part of being human we cannot remove. The issue arises when the ego tries to retract/protect itself, rather than embracing the emotions, dealing with them/seeing them rationally, and moving on. I would get caught up in the "loops", but all that was happening was an imbalance of focus towards that, distorting the individuals perspective as a whole. Learning to accept it as it happens, that you have to deal with it
at that moment as it is, and move on. Other wise it gets amplified beyond rational/realistic proportions in relation to the "good" feelings you get sober and on psychs.
"let those who have talked to the elves, find each other and band together" -TMK
In a society in which nearly everybody is dominated by somebody else's mind or by a disembodied mind, it becomes increasingly difficult to learn the truth about the activities of governments and corporations, about the quality or value of products, or about the health of one's own place and economy.
In such a society, also, our private economies will depend less upon the private ownership of real, usable property, and more upon property that is institutional and abstract, beyond individual control, such as money, insurance policies, certificates of deposit, stocks, etc. And as our private economies become more abstract, the mutual, free helps and pleasures of family and community life will be supplanted by a kind of displaced citizenship and by commerce with impersonal and self-interested suppliers...
The great enemy of freedom is the alignment of political power with wealth. This alignment destroys the commonwealth - that is, the natural wealth of localities and the local economies of household, neighborhood, and community - and so destroys democracy, of which the commonwealth is the foundation and practical means.” - Wendell Berry