It's a very widespread idea that if you have personal experience with a psychoactive drug, this biases you in such a way that the research that you do is not trustworthy. But this is something that we don't evenly apply to other disciplines. No one would ever say that an ethnomusicologist is biased because they've listened to music or because they enjoy music themselves ... Instead, we would say that this is something that makes them an expert who is qualified to discuss the subject.