Liam's actually much more chill about the existence and doing of drugs now-a-days, He might even be doing drugs right now for all I know. The odds of that aren't necessarily astronomical, but they're certainly higher than they would've been for the two-years-younger tyke you see in the comic above.
I wouldn't say that I necessarily introduced him to the world of drugs; though, perhaps I introduced him to the concept that people who do/have done drugs aren't instantly transformed into burnout losers, but you'd have to ask him about that yourself.
Maybe I'm not the best case for a "non-loser" but I hardly think my rare, sporadic drug use has contributed to that. I'm my own loser damn it!