sorry but I think you are not considering history and data here... sheep and goats were selectively bred by humans and often cannot survive without us. Modern (domestic) sheep and goats are veeeery different from their wild ancestors (e.g. traits vital for wild survival got removed). The idea that "they survived history, they will survive forever" is a classic logical fallacy. Many species survived for millions of years right up until rapid environmental shifts/new pressures drove them to extinction (e.g. see the pyrenean ibex). Moreso: modern habitats have little resemblance to historical ones. Wild deer/goats/sheeps evolved in vast, connected ecosystems! With human development (highways/agricultural fencing/climate change) today we have severely fragmented habitats: natural migration routes are no longer there. So a lot of these "survived thorughtout history" animals can get easily squared / hunted down