If I understand your comment right, you are saying that the opiod crisis shows that people do choose drugs if they can and if there was univ. healthcare, then the system would go down under the costs.
The problem with this, as I see it: A good chunk of people addicted in this opiod crisis didn't choose to get addicted. They were all too readily prescribed hard painkillers for ailments that did by no means require such a treatment (e.g. backpain of various degrees). This is fentanyl as a gateway drug, so to speak. Those people would not have been addicts otherwise. But they got hooked on the medication and when their prescriptions comes to an end, then they would seek a replacement.
That is why doctors and pharmaceutical companies are getting sued - and are losing.
Further: If psychedelic drugs are indeed this helpful with issues like smoking and depression, like recent research suggests, then controlled administration would surely be a great relief to an overwhelmed healthcare system: saving e.g. on expensive anti-depression drugs or on cancer treatments, where the cancer was caused by smoking.