This has been an interesting discussion, along with any number of allegations not citing any studies.
I had heard long ago that about 10% of those who drink could be classified as alcoholics. The National Institute on Alcohol abuse notes that for the age bracket of 18+, 6.2% of those adults have AUD (Alcohol Use Disorder).
There is no particular reason to presume that the % of abusers of marijuana is going to be significantly higher. Yes, there are going to be some who become “stoners” and seek to be significantly affected by their consumption; the same goes for alcohol. But just because some abuse alcohol does not lead to banning it for all who drink recreationally, the same applies to those who smoke recreationally.
People consume marijuana, to put it in their own terms, to “mellow out”. There are exceedingly few cases of violence by someone who has smoked; but with other “harder” drugs, there are any number of cases of violence and crime committed.
The Church has made a prudential judgement, just as Pope Francis has made a prudential judgement on capital punishment (and I would be happy to cite a case which flies in the face of his comment about it being “inadmissible”, in spite of the fact that I am against it).
What is likely to happen is that the Federal Government is likely to remove marijuana from the list of prohibited drugs and leave it up to the states to determine what, if anything, they choose to do to allow/control it. it will then be up to the states, and to the individuals as to whether and to what extent they use it.
Johnson and Johnson has set up a lab in Canada to do research on it. Coca Cola, Pepsi, and various large alcohol conglomerates are all looking at the issue, and some have invested seriously in some of the Canadian companies. In essence, it is here to stay.
We have any number of people “virtue signaling” about its use; many of the same people will have a drink or two (in other words, in moderation). On an empty stomach, one may feel the effect of alcohol with only one drink; with two, very likely will feel some moderate effect. I simply point out that the effect of alcohol is noticeable but not great for most, and many if not most marijuana users are not seeking a “Cheech and Chong high”, just as many if not most drinkers are seeking a bit of the effect of alcohol.