I mean...on that note, there were plenty of real life warriors who wore clothing we might consider skimpy...not every culture invested in covering their armies with actual armor. And even in cultures that did, many fighters went without: good armor is expensive and needs upkeep.
And I dunno, just in general I'm inclined to disagree with someone saying that they're tired of certain characters being portrayed as competent simply because they don't dress "correctly". You don't have to answer to me, but I will question that kind of thinking.