Holotropics has been around for quite a while and some yoga pranayamas also can lead to altered states. I have to admit I find mushrooms easier to deal with.
Elitism and snobbism in spirituality and meditation circles is real!
One method is adjusting CO2/O2 levels. And if Yoga, you are moving and there are body/mind connections, even weight lifters can experience this. Even just stretching.
Versus laying on the couch on drugs.
Psychedelic's do "something", but not the "same thing".