I'll try for them, because i think they missed the main counterpoint:
Every single person's reaction to mind altering substances is different and unpredictable, because each person's neurochemistry is unique and not currently well-quantified. What might affect you deeply could literally have the opposite effect on me just because my brain is wired differently. This is why multiple different mind-altering substance prescriptions have to be tested to treat things like anxiety and depression. The same dose of the same strain of marijuana will have vastly different effects on even a small sample of people, and expecting someone who's trying any drug for the first time to just "google it" as a matter of policy is not just delusionally naïve, but potentially dangerous to the point of negligence.
TLDR for the longest thread I've ever been a part of: Amnesigenic comprehends precisely none of what I say, and for some reason thinks that anything that doesn't kill you is an axiomatic moral good, and that that's somehow relevant to their claim. Read on at your peril, because here be idiots. One of them is a block-headed knuckle-dragger, and the other is an idiot because he thinks that trying to respond with actual argumentation will get the other idiot to give up or actually respond with a relevant point. I'll let the reader decide which one they think I am.<\edit>