The problem it's not just the people that sell drugs rather those who patronize these people selling it.
When we are in a society that is broken, people look for a way to just escape pain and stress and drugs is the closest way to achieve that. If you want fear of overdose of these drugs, we need better mental health care, we need stable jobs, we need schools, affordable housing, and we need support from the government and there must be policy to focus on punishment. Severe ones.
If someone is caught with this, and we should also invest in prevention, not just arresting of people engaging in these drugs.
I think that is the only way to shrink the demand or make the drug market collapse.
There should be severe punishment of governments that aren't working in the best interest of the wellbeing of it's people.