Is robitussin kind of like the padded glove used to cushion adolescent kids half ass suicide attempts?

Of the things ive seen in my time, it seems like a large number of adolescent boys and girls (although more so girls) want to have a suicide attempt in order to garner love/attention from their parents. Ive seen vids of young girls talking about their brush with death when they drank a whole bottle (it would take orders of magnitude more to actually kill you) of robitussin dm.

my tin foil hat theory is that robitussin is a fail safe protection that is used to pad the landing of troubled teens so they dont take the route of buying heroin or fentanyl on the street and overdosing.

im not hating on these teens, im just curious as to why a drug like robitussin (dextromethorphan) is legal even though tons (tons) of kids use it to trip balls.
in my view it would be better and just as safe to offer opium cigarettes at convenience stores.
if you get too high on an opium cigarette, you pass out and the cig falls out of your mouth so you dont overdose.
That was the thinking behind the fentanyl lollipops from what i understand.

**This thread was edited on Feb 3rd 2020 at 11:43:14pm