This is the idea behind basic income. Basic income eschews the oversight of traditional welfare programs so people are free to spend their money on food and drugs with less pressure to pick one over the other
UBI, an employer of last resort capable of enforcing a minimum living wage, specific support for those who cannot manage their own affairs or be addressed solely through additional money, and a land tax to put a cap on housing appreciation and costs, as well as to spur denser development. Oh, and jettisoning anti-density zoning and building codes.
I'm not sure that's sufficient, but I think it covers a broader set of issues than approaches of the past 40-50 years have managed.
I'm not speaking from an ivory tower either, like many UBI supporters seem to do. I grew up with friends who were addicts. Ive known people who died of overdose. Plenty of kids are more than happy to throw away their lives smoking weed and shooting up, especially if they're getting their shit for free.
For the record, I support responsible drug use. But UBI is not the answer for the problems in our society, because it will hurt many if not most of the people it should protect.
Ibogaine.
The US classifies all hallucinogens and psychedelics at Schedule I, so obviously no researcher that values their academic career can study the use of psychedelics for the purpose of curing addiction. But anecdotal reports suggest that a heroin addict may be cured of opioid addiction by using kratom to alleviate the physical symptoms of withdrawal, and ibogaine to "reset the brain" to no longer desire heroin.
Politically, people would prefer to believe that rehab centers actually work. Using illegal drugs classified as "the worst, most dangerous drugs in existence" to cure addictions to other illegal drugs with a lesser classification may be perceived as... a bit hypocritical.
UBI would instead need to give everyone above the drinking age something like a monthly ration of 2 ounces cannabis, 2 psychedelic doses of a regionally appropriate entheogen, and 750 mL neutral grain spirits, all from local production facilities. If they want more, or better quality stuff, they'll just have to spend their pocket money on it, or get a QA job in the industry.
Also, giving the actual drugs out can influence the market, such that people may be encouraged to use drugs that are more socially manageable--in contrast to opioids. Honestly, I'd rather hand out free weed than free alcohol, but you just know the agricultural lobby will heavily influence the composition of the UBI goods ration. If they can make your fuel 10% ethanol, they can certainly convince the government to distribute some of that distilled corn alcohol for human consumption.
You also pick really weird amounts. A casual drinker can kill a fifth in a weekend without really disrupting their life, while they range in price from ~$5 (after taxes!) to $25 (Smirnoff is $14 here).
Almost no one would use 2 ounces of marijuana in a few days and it has a street price in the hundreds of dollars.
750 mL works out to about 17 shots of 1.5 oz. each, but I also figured it would probably taste like it was made from stale tortilla chips in most of the US, and would therefore mostly go into mixers, averaging 4 drinks per week. The people who really enjoy their alcohol would be springing for commercial vodka, and there would also be plenty of people who would be getting that ration and not drinking all of it. Many drinkers would probably be relying on a beer or wine ration, but I don't really consider those to be "drugs" below a certain %abv, and UBI beer would probably be around 2.5%abv, with the wine around 4%abv. The beer would taste like a business handshake between Bud and Miller, and the wine like Welch's made out with Manischewitz on their friend's couch.
And for the peyote buttons, mushrooms, DMT or whatever, I thought two trips in a month might have been pushing it, especially for people that were still trying to have normal jobs with their UBI. Good for two of your four weekends, with maybe a couple sketchy Mondays when the machine elves follow you to work.