If you had access to some of the most compelling women of our time, you'd think you wouldn't waste it with pointless questions. Then again...
Interviewers could ask any of these women about current events, hobbies, or, you know, about the movies they're in. But they don't.
Actresses often get their dresses for free for the mutual publicity, but it's not all about "who they're wearing" (which, by the way is a really strangely sexual way to ask which fashion label made their dress). Those outfits parading on the red carpet are on some pretty stellar ladies, not hangers.
Actresses are hardly ever asked about their motivations behind their roles, but I bet we could make a supercut of male actors being asked just that question.
Why don't more people ask Viola Davis about her mother, who was a civil rights activist, or Anne Hathaway about her LGBT activism, or Cate Blanchett about anything but "who she's wearing"? I'm pretty sure any question you ask her would be interesting because Cate Blanchett is the best. But if you'd like me to be specific, you could ask her about feminism, because she's been outspoken about that before.
And why don't they ask the men who they're wearing?