Frankly, it doesn't surprise me that you would let arrogance about your knowledge of drugs get in the way of the obvious here: Not all drugs are created equal. That is what is wrong with our war on drugs. We treat them all equally bad. That is not the case.
I don't recommend applying the exact same standards to each and every drug - I would just urge caution in making such a distinction between, say, cocaine and methamphetamine when they both produce similar effects. At the end of the day, my main concern is preventing needless deaths. Meth prohibition does not accomplish that, nor does it even come close to doing so.
If you know meth users and their use of meth has not harmed them or anybody around them and they can quit and restart again at their own discretion, then I guess I'll eat crow.
Honestly, I'd be surprised if you
didn't know someone who has tried methamphetamine without ever getting addicted to it.