I am not just talking about addiction, I am also referring to the physiological damage it does.
While it’s possible to cause significant damage from a single overdose I don’t think it is likely from trying something at a sensible dose once. Most of the time the damage addicts have is done through repeated heavy use.
Also, afaik, alot of the damage done by things like meth and heroin are side effects. Like meth gives you psychosis and brain damage from staying up for days and not eating any food. The long term effects of meth, like a rotting mouth and permanent chemical imbalances can take years to manifest. If you want an example see people who take Adderall for years. Heroin similarly stops you from getting proper nutrition because all you want is heroin and it can give you brain damage from a lack of oxygen, which is a side effect of getting really close to overdosing.
As you’ve said, most people (at the very worst a whopping 70%) try these drugs and continue with their life without getting addicted. It’s very dangerous to stigmatize them cause all it does is make people afraid of getting treatment.
Trying drugs once rarely does any psychological or physiological damage after one or even a few uses.
There are few cases where taking certain drugs will trigger the start of people already prone to things like schizophrenia… But it takes a while for legit psychological and physical addiction with few exceptions. Even with the most addictive drugs there are.