Watching a youtube of folks crossing streams - I think in Sierras, but could have been farther north. Lots of snow, so you know, when they come out, they are wet and cold.
What do you do at this point? You need dry clothes, and you need to dry your wet clothes, right? So are you stuck here for a while or maybe till the next morning? On a cold day out there, are the wet clothes going to dry? (Many places, there are campfire restrictions, and it's probably going to be pretty tough to start one anyway)...
How much weight does winter clothing add, if you're on a PCT thru-hike?
How many times are you going to face this situation?