The mountain goat is a distant cousin of the Old World goat which lives in many environments in the northern Rockies and other mountains of the Northwest of North America. They are similar to feral goats, albeit larger, and to some degree meaner and more ill-tempered.
Goats were an early domesticate of Old World civilization, and very widespread as they are useful for their meat, milk, coat, and even for pulling carts in remote areas. The slightly larger mountain goat seems like it could excel at this too (although I have no clue how much milk a mountain goat produces, at least compared to a wild goat or other non-milk goat breed).
IOTL the Salish peoples of Washington were known for gathering mountain goat wool which had been shed thanks to the goats rubbing up against trees and walking through bushes. This is an interesting use of the goat, and the Salish were also generally sedentary thanks to the wealth of their land.
If the Salish population boomed while the mountain goat population shrank for whatever reason, or the some other domesticate arrived to "inspire" goat herding efforts (i.e reindeer), would they be a good candidate for mountain goat domestication? Or perhaps the Tlingit or another group toward their northern range which I'd imagine would have smaller mountain goats (less dangerous) due to less food and colder winters?
So if we presume a chance domestication of mountain goats at any point in the last 1,500-2000 years, what would the effects on North America (and beyond) be? Are mountain goats potentially revolutionary in that they could spread fairly widely and create much more resilient native civilizations all the way up to southern Alaska and the Yukon?