At no point did I say "don't try to solve the drug problem". I even said as much when I said "help the homeless get their life back on track". What I'm trying to say (and clearly failing at saying) is that "don't even bother with 'x' until we accomplish 'y'" misses the fact that at least as it pertains to dealing with making cities people want to live in, its a complex, interrelated system. In my, highly limited experience, for instance, homelessness drives drug use, because its a relatively cheap escape from the desperate reality of homelessness and long-term unemployment. I'm not here to make excuses for people, but I am here to say that its a lot more complicated than "get rid of the drugs, and people won't be homeless". If it were that easy, then Reagan's War On Drugs would've actually, you know, worked.
You should educate yourself on the root cause of the US's opiate problem. While there a lot of recreational drug users who went off the rails, virtually all of the addicts I know personally were initially wildly over-prescribed opiates for a legitimate medical reason, and in trusting their doctor, got addicted. There was a big court case around it. I know, the plural of anecdote is not data, but there is in fact data about it.