animals suffer more being killed by a predator animal than a hunter. But that is an unfortunate result of evolution, animals that must kill to survive. Humans are not one of those animals though.

How are humans not animals that evolved in a way that we must kill animals? For the vast majority of human history we did. Relatively recently only we didn't (~12000y ago), though we still hunted after agriculture, and raised animals to eat, so it's debatably maybe the last maybe few hundred years only, or maybe as late as ~100 years with global commerce.

Sure, we maybe don't have to now, but we did evolve needing to. Us not needing to isn't evolutionarily created, but an artifact of modern trade and industry. It hasn't been long enough to really affect our evolution.

Also, as much as I'm against factory farms, I don't know if we're even at a point where we could farm zero animals. Stuff produced by animals is still required for many things. We should work to reduce it, but I don't think we can be at zero yet most likely.

Edit: I have a somewhat unrelated question that I've been curious about from a vegan's perspective. How do you feel about eating oysters? They can't feel pain or anything, so in my opinion they're one of the most ethical sources of protein. They are technically an animal though. I don't know if you've ever thought about this, but I've been thinking about it a lot. In my mind they're essentially a plant that's made out of meat. In fact it may be more ethical in many ways than some plants that consume a lot of resources.