I completely disagree with this. Our agriculture has reached the point where we no longer need herd animals to convert inedible grasses into edible meat for us. We don't even really graze our herd animals anymore. We feed them foods which are also edible to us. Raising animals for food wastes a lot of arable land.
From a Darwinian standpoint, human consumption of animals is very beneficial to the animals themselves. It isn't good for us. And it gets worse for us as the population rises. There is an increasing paucity of food in the poor areas of the world. There are food shortages. There is a great deal of starvation.