Not just the clothes, but the tents, ropes, shoes, bags, gloves, etc have all improved (and gotten more plastic). There's a bunch of metal waste too (oxygen cans etc) from what I understand, but at least that's mostly metal. And lots and lots of frozen poop and corpses, I suppose. It'll be interesting when it all melts...
Real expedition mountaineering is definitely not a lightweight endeavor even if there's more high fill down and other better warmth/weight ratio clothing. It's more about trimming a few pounds off the weekend (or longer) hiker/camper's weight budget.
