EDIT: As the father of three daughters, I'm much more concerned with my daughters consuming too much alcohol, which puts them into a compromised state of decision-making. I know those drugs exist, and have been used, but alcohol is much more prevalent, much more socially acceptable, and just as effective at reducing decision-making ability, and ultimately, the physical ability to resist unwanted advances.
That being said I'm pretty sure every teenager will get way too hammered at one point or another, it's a quintessential teenage experience.
While one shouldn't exactly encourage drinking, responsible drinking is part of our culture so allowing that for teens at the appropriate age (in Germany 16 and above) at home is the best way to give them the necessary experience and also being able to give advice where needed, as this then isn't a "taboo" topic.
The solution for that is proper education about its effects and about knowing their own limits.
"When to leave the party" is knowledge everybody should have.
I am aware they wrote that facetiously, but the issue really is about detecting things you don't want in your drink, not changing people's choices about what they want to consume.