There probably are reasonable methods of estimation that would say suffering associated with factory farms currently outweighs suffering occurring in the wild, though I don't know if I agree. However, factory farms are both relatively recent and temporary. It's hard to defend the position that humanity vanishing tomorrow would reduce net suffering in the long run. If nothing else, another industrial species will eventually replace us, and there's little reason to believe they'll be any better.

Of course, I personally have higher hopes for intelligent life than merely not causing massive suffering. That brings me to another tangent: Are you vegan?

I am. You might be, but I'm estimating you probably aren't. You can go vegan, it's easier than you think, and if you don't think you can commit, being 90% vegan is 90% as good as being 100% vegan. All thought experiments aside, you can be a part of making a better world, right now.

You can also make donations: https://funds.effectivealtruism.org/funds/animal-welfare

I think humanity did introduce evil.

It requires a sense of morality to divide good from evil, and I don't think that existed on Earth before humans. Digging into the Hominid tree might add some qualifications, but I don't see that as a meaningful distinction.