[saalweachter]

Refrigeration is to blame as much as anything.

Raising a cow is only a part of the problem, and it isn't that much harder to raise 10 cows than 1 cow, if you have the acreage. O(log) at the worst.

Butchering and preserving the meat was the O(n) operation, and usually required O(n) resources to salt or smoke, which could be expensive resources depending on your time and place in history.

Refrigeration changed the game, to where we could preserve the meat as fast as we could butcher it. Now instead of spending days or weeks salting, canning, smoking or curing your meat, you can fill a freezer in an afternoon.