All good points.
There is physical addictiveness to alcohol. There is psychological addictiveness to marijuana. The health and mental and behavioral aspects of the two vary widely.
I’ve known several people, personally in my lifetime, to drink themselves to death. I’ve known of one person who smoked themselves to death by overdose of carbon monoxide from pot...somewhere in Britain, according to an article I read. I’m sure there’s plenty of extraneous connections to combining these drugs with other drugs and destruction of oneself and others.
Of course there’s many ramifications for abusing any drug.
There are so many mind altering drugs, both legal and illegal, and both maufactured/concocted and naturally originating.
Regarding the brain, it seems to me, I know many people whose brains have been utterly destroyed by psyche meds than any other type of drugs...to the point where they are in a constant battle to thrive in the real world. Their brains’ chemistry have been permanently altered and they will never be “normal” again. There is a host of diabetes and metabolic disorders resulting from their use - as prescribed. I feel the numbers/percentages of these people far surpass the pot smokers and alcoholics. 7% of schoolchildren are already on them. 25% of the female population and 15% of the male population take mental health related medications.
If people are really concerned about the “level of productiveness” of our society/culture, they will of course need to be first concerned with these medications.