Sam Harris states that you can achieve this enhanced selflessness via meditation (where we think of the "self" or "the ego" as that sort of "conductor" that the psychedelics turn off). However, while meditation is like a sailboat, psychedelics are like a rocket: both will take you places, but one much more quickly and with much more risk.

In my limited experience (2 trips) there was no negative aspect to psychedelics. There were things that were already negatively valenced, like riding in a car or visiting a friend's messy house briefly, however I had no inkling of a bad trip or any scary/demonic/overwhelming sensations.