Yet if we compare the regulated drug market to the unregulated one (mostly perscription painkillers vs marijuana) the regulated market has arguably worse outcomes and higher costs.
Also, Kurz Gesagt has a great video on addiction--it's not as simple as blaming the problems/externalities solely on drugs: https://youtu.be/ao8L-0nSYzg
My assumption is that most recreational drug users are choosing caffeine, alcohol, marijuana, perecription painkillers, perscription amphetamines, probably in that order.
I know heroin use exists, but I've never personally met a regular heroin user in my life. So my comparison is the regulated vs unregulated market broadly speaking and representative of what's commonly being consumed.
If you watched the Kurz Gesagt video, there is a point to be made that extreme disassociative addiction is rooted in unhappy life circumstance, not in the drugs themselves.
Personally I could be in favor of some regulations around heroin, but the ones we have now create more problems than they solve.
The sale and consumption of sugary drinks is not victimless either, but there's a multi-billion dollar industry behind it.
You're making a great argument for regulating Coca-Cola. (And it's one I happen to agree with.)