FWIW - I am "too far south" in Canada to legally run studs, they simply aren't permitted as they do too much road damage. I admit I'm scratching my head a little to figure out how "south central US" (not sure just where all that might be) has so much more demanding winter conditions than I see and concludes that non-studded tires are useless. In my area I do drive in a lot of brine and salted slush as opposed to true untreated ice and snow, and I often think it's too "warm" for Hakkas here.
Unlike most years, this Feb we've been getting "cold snow", where it's actually *well* below freezing when it snows and the snow is "dry". I had some real trouble with AWD and Hakka R2s on my street (but not the street one block over, closest access road, or my SO's neighbourhood 2 miles away) because of the exact combination and timing of salt application. It was fluffy white snow on a base layer of thick greasy stuff salted hours earlier. Almost zero ability to turn or stop - touch the brake pedal and ABS goes absolutely bonkers. Generally I've found this combination to be my nemesis in winter traction and studs wouldn't help a bit. It's caused by the regional tendancy to solve all problems with salt instead of plowing it aside and otherwise leaving it alone for a while. As soon as I left my street where the salt/plow timing and quantity was just a little different, even though it looked identical out the windshield, traction wasn't an issue. In areas where surfaces were near "virgin" (no salt and driven over between zero and a couple dozen times) I had tons of grip.
I guess I'm here to say non-studded tires are anything but "useless" and studs only help on glare ice, and most on warm, wet ice I believe. I suppose if that's all you see in "winter" driving, you could conclude that anything except studs was useless. The government considers my winters not severe enough to even allow studs as an option. I have to drive a couple of hours straight north before I get to an area that permits them. When purchasing studded tires or when pulled over or inspected, you have to show ID that you have a residence north of a particular line. I have definitely considered studded in the past, going against regs.