Earlier quoted context omitted.
That is not why fentanyl kills.
Fentanyl is administered daily by medical professionals in all sorts of situations. If "not understanding it's strength" is not what causes people to overdose on it, then why aren't millions of people dying from its administration in a medical setting?
If by "regulation" you mean "restriction", then, sure, I buy that, stipulating that it's somehow possible to restrict access. But what the preceding commenter meant by "regulation" was labeling. No, that won't work.