The circular sock knitting machines, as pictured on the site, absolutely make high quality socks. My wife has a niche business teaching classes on how to use those machines, making and selling socks, etc.
The part that would be missing from a wind-powered solution is the actual shaping of the sock. She spends a lot of time as she works futzing with the hooks on the machine to create the heel, toe, ribbing, etc. I'm not an expert in what she does, but I see enough to know that if this is just a turbine spinning the machine, you'd get a uniform tube, which would then be post-processed into individual fairly shapeless socks. Hand-crafting would shape the socks better, but the basic tubes are high quality even if unshaped.
There is also definitely a niche-within-a-niche of people who work on these machines coming up with all kinds of non-sock applications for well-knit tubes of fiber. Scarves are an obvious one, but re-working different sizes of tubes to create stuffed animals is one of the more fun ones.