Drug dealers secretly cutting their usual supply with fentanyl. I think so few people are talking about it because the most obvious answers are the hardest ones.

Sanction China? Might lose the ability to import a lot of goods, and China can just drop them off elsewhere to get around sanctions.

Make it easier to get the less bad form(s) of whatever a person is addicted to? Requires careful crafting of legislation and enforcement to ensure you don't create new addicts or undermine addiction recovery.

Go back to "Just Say No!"? But I thought that didn't work for some reason.