Here is a little bit of recent research I found when studying new curricula for my nursing students:
About 40-45% of the usable land on Planet Earth is devoted to raising animals for protein. This percentage is comprised of direct land use (feed lot, grazing, barns, milk factories, etc), and indirect, as in growing grains and grasses to feed the animals.
All the worlds protein needs can be met with only 2% of the usable land if we convert to an entirely vegetable diet. I suppose some land will be devoted to feeding race horses, grey hounds and whippets!
Now, my sister-in-law is an off the deep end fanatical vegan. Her husband just commented how he spent the Holidays eating all vegan. He said "I'm done with this," and swore to resume his meat based diet. And I must agree. Every time I abstain from beef, then after several weeks eat some again, I'm blown away by the flavor.
Intellectually I know we must adopt sustainable and humane food producing strategies. Enter synthetic meat. There are a zillion articles, some very outdated. Synthetic meat is being produced now, but of course, is still much more expensive than real meat. "Food scientists" have isolated the chemicals that make meat taste like meat, then they synthesize the proteins in the lab. Hence names like "test tube steak" and "Petri dish pork". Testers in London (and elsewhere) say they love the flavors, but not the price.
I just think about my off the deep end fanatic vegan sister-in-law. I doubt that would be a solution for her. If the price came, I see it as the perfect solution for us carnivores with a conscience. All the flavor I want, none of the heart issues, all the environmental consciousness, and without the slaughter of animals. Here is a Gizmodo article
(I think it's NOT commercial - please do not clobber link).