Maybe some hardcore schmoe can answer this, but exactly what year did this become a cool thing to do? I don't remember it in the 1970s or 1980s. Was in the late 1990s or the early 2000s? I know it has become a running joke here but is anyone really winning contests by showing shredded glutes? Why can't we go back to trunks instead of thongs?
go back to the 70's. everybody wore full briefs. something you could wear to the beach. you still could tell who had the striated glutes.
Bill Grant and Tom Platz come to mind. you don't need a thong to tell if the glutes are striated.