You're welcome!
I think people assume briefs, especially white ones, with childhood. When I was little (I was born in 1990), that's what the other little boys and I wore. When I was in the 5th grade, I started wearing boxers. Boxers were "adult" underwear. I started wearing boxer briefs when I finished high school.
Also older men (60+) will be seen in briefs, which I think is another reason why they're not that popular. For me, boxer briefs are the most comfortable. I've tried briefs as an adult, and I was not a fan.
