> someone uneducated about it who is really suffering could easily take 3 or 4 times the dose.

And the solution is simple: educate people about that.

And it's not something hard to do, just have pharmacists say “respect the dose as it will kill you if you don't” every time they sell things and it'll work.

But Tylenol/acetaminophen/paracetamol is an over the counter drug, so there is no pharmacist involved in most sales. And I certainly wouldn't count on everyone reading the tiny text on the bottle.