For the most part, no customer wants fentanyl. The dealers like it because it's a cheap booster for cutting the drugs that their customers actually do want to buy. It just has this unfortunate side effect of making small overdoses lethal.

That's why "ending the fentanyl crisis" is a curious goal. We had a perfectly good War on Drugs going on, but fentanyl is making the illicit drug industry too dangerous. You'd think that if we wanted to stop drugs, and we knew how to do that, we'd stop drugs. Instead we're stopping fentanyl, so we can get back to the regularly scheduled version of the War on Drugs that was always intended to last forever.

Do you mean that drug dependence has become more visible? That petty crime has increased?

One fun thing about harm reduction policies is that, as a result of fewer people dying, more people are on the street. So while you don’t see people in the morgue on your daily commute, you do see them down the alleyway. This side effect may be more unpleasant for you, but that’s only because you’re not personally inconvenienced by the corpse sitting in the freezer at the coroner.

But we still have a depressingly large number of alcoholics. The campaign against drunk driving has helped reduce one set of negative side effects, but not others.

There are still legal ways to have a gun in Australia and many other countries that “ban guns”. They don’t have total bans, they just have more restrictive regulations than the United States.

Consider how we regulate alcohol or marijuana as examples of how legalization of drugs works.

https://en.wikipedia.org/wiki/Gun_control