Non-cow milk has been around for years - soya milk, almond milk, rice milk, coconut milk - and then from farming enterprises in NZ with animal alternatives - ie goats milk and sheep milk on a small/growing scale, priced well ahead of cows milk. There has probably been some traction of non-cow and plant dairy in recent times but would suggest that has still been relatively small.
(Sorry couldn't find the article with the link)