"Factory farms are not what animals evolved for, so the unnatural conditions in which they're raised very likely induces suffering and pain in the raised livestock."
What makes you think that "natural" means free of suffering? Nature is spectacularly cruel. Many domestic animals (think well-loved family pets such as cats and dogs) live lives incredibly free of the suffering of their non-domestic ancestors.
It is certainly possible to raise animals for food where they have an easy life, and feel no pain at the end. I can't speak to whether it is economical (obviously, ensuring this would be expensive), but still. It is NOT impossible, or really all that difficult.
If you want to make the argument that killing animals with brains is bad, fine. I can go with that, and would prefer meat that doesn't involving killing. But basing it on false assumptions about how much pain the animal must experience is just going to make me say "let's just make laws that say animals must be treated very well and have a perfectly painless and stress free death."
Because I'm just not convinced, at all, that a well treated animal automatically suffers more than one in the wild.