I honestly don't know but briefs would be way more popular with the elder gent ( by which I mean maybe generation above me ) especially in Europe . My generation was the first to start really wearing boxers - I have no idea why.
Of course. It's tighter so no saggy balls. Win-win!
Im 51 & only wear briefs, tried boxer & didn't like them, didn't like the way the felt under my pants, for various reason. I dont wear grandad pants, i go for sloggi start midi briefs, mainly for the colours, style & support. I had a girlfriend once say to me jokingly i was too old to be wearing underwear like that. Briefs can be sexy, depends on what style you're wearing, plus older women dont seem bother about that.