I'll save you the time (though you should watch it).
1. Much of the animal feed comes from agricultural byproducts. As an example, we eat corn on the cob, but much of the corn stalk is inedible to humans, but can be made into products for animals.
2. Much of the land used for animals is not suitable for growing crops. Some is, but it's not a 1:1 swapability factor.
There was a recent Youtube video that explained how this isn't quite accurate:
https://www.youtube.com/watch?v=sGG-A80Tl5g
I'll save you the time (though you should watch it).
1. Much of the animal feed comes from agricultural byproducts. As an example, we eat corn on the cob, but much of the corn stalk is inedible to humans, but can be made into products for animals.
2. Much of the land used for animals is not suitable for growing crops. Some is, but it's not a 1:1 swapability factor.