I have heard people claim that if you don't purge it doesn't count. It's the first thing they ask about another person's experience. That always felt a bit like Stockholm syndrome to me.
The argument above is exactly the same with the same qualifier that of course not everyone (or even many) hold that attitude.
It's not really comparable.
Sometimes the medicine has to be pretty bad to fight off something worse!
The argument is that the vomiting is a necessary step of this powerful medicine, and that the medicine is curing mental disease.
I'm not defending ayahuasca, I actually do think it's a sketchy corner of the psychedelic world to be trodden on very carefully, if at all. Just trying to supply the perspective.
Ayahuasca (to some people): wot you didn't vomit? if you didn't vomit, it never happened.
I have heard people describe ayahuasca purging as getting rid of mental and/or physical toxins... as getting rid of depression, emotional/psychological baggage, medical maladies, etc..
Am I on HN or Shroomery?