<<<Have you ever walked through 135 cm of snow?>>>
Well, yes. I've also climbed over and fallen through 8' (2.6m) drifts to get feed to, or to dig out, my animals. We don't often get as much snow as other countries, being a maritime climate, but sometimes when the wind comes from Siberia, then picks up a chunk of the ocean, we do get some snow, very wet and heavy and difficult to clear. We probably go on about it more than other countries, and the press builds up a light dusting into a major fall, because we get such varied weather that we love to talk about it - it's different every day, and often within one day. Then when it is really cold, we do need the warmest clothing.
Sorry I can't help with goat hair. I use Hebridean sheep's fleece, which is double, for boot socks, as the inner layer provides warmth and the outer, hair layer provides strength, but I'm sure it doesn't have quite the warming qualities of goat.