For sure the it's popularity is due to peoples' sense of fashion and pataguc's branding but if you use something like this combined with a good base layer, a windshirt and waterproof layer (marmot precip) you've got a system for all except the coldest conditions. When it gets real cold just add a belay jacket or down parka.
My system is pretty much just like this but I am not a fan of softshell jackets at all. They're way too heavy and way too prone to soaking through in rain and wet snow. Even the term sofshell is BS they should be called hardfleece because they offer no performance improvement over a fleece jacket with a windstopper membrane. Schoeller is great for pants but sux for the upper body IMO.
Talking about fashion statements; how many poseurs are running around Seattle in their $300 softshells.