It’s like this with most animals that we have learned to live with in close proximity. Zoonotic viruses are responsible for many of our diseases today, but through natural selection we are adapted to many.
This is partly why European disease wiped out Native American populations to a large extent. Europeans carrying diseases from animals they lived closely with.
But it's not (just) about us living in close proximity to them, it's about putting them in an environment that makes it impossible for them to live healthy lives and incubates potential zoonotic diseases.
We have not been factory farming for centuries. More like a century. And it hasn't been a century with a sterling track record! I think we can all recall an event in recent memory where having a lot of animals in close proximity and unhealthy conditions went super duper wrong. And we have problems with new strains of bird flu every couple of years.
People used to literally live with the livestock attached to home or even under the same roof. This was probably the case for most of agricultural history.
Factory farming is bad, over use of antibiotics in live stock is bad. But OP's point is that this is how many of the diseases in human history and therefor unlikely we would ever be able to avoid this while raising animals for food. As they said, both are true
I can't speak for OP, they may have been advocating for giving up farming animals (or fowl) altogether, but personally I see a huge inflection point between traditional and factory farming methods with regards to the level of risk. When you are compromising the immunity of your livestock, you beg trouble.
I understand the temptation to zoom out to a several hundred year timespan, that can be clarifying. But when (as in this case) there are substantive differences in recent history, it muddies the waters. I totally buy that endemic diseases are largely zoonotic diseases plus time. But that doesn't clarify how much risk exists in our current methods of farming. Factory farming is not equivalent to traditional farming in this respect. History is not featureless and when we flatten it we lose important details.
Living in close proximity is one thing, but growing them at the speed and scale which we do with factory farming must massively increase the rate of development of viruses. It’s almost as if we designed a special program just to develop a virus that would wipe us all out.
Yeah. It's very cheap to grow large amounts of canola seed, soybeans, potatoes, corn, and wheat to make all manner of high-salt, high-fat, high-carb junk food.
It’s even cheaper to just eat the potatoes, corn, wheat, soy directly like humans have at least for 1000s of years. It would also be healthier and less damaging to the planet as well as local environments, and save tens if not hundreds of billions of animals lives.
The processing is simply unnecessary and the output isn’t food but essentially drugs that people get addicted to. That’s completely different from the actual food that we grow.
This is partly why European disease wiped out Native American populations to a large extent. Europeans carrying diseases from animals they lived closely with.