I’ve always thought the trope was based on the idea of stunted development. Kids are heavily encouraged to drink milk, so films making a point of adults drinking it are indicating that there’s some part of growing up that they’ve missed.

I feel like back in the day trolling was more of an art where you’d say something stupid to expose someone’s cognitive dissonance.

Now it just refers to people being dicks. Trolling itself has become enshittified.