While I agree with the food poisoning argument, I disagree with the disease vector theory. We have bird flu but no ancient cultures banned chickens. We know about rabies but we still keep dogs.

The other point we need to remember is that by the time ancient people knew about a disease, it is probably an epidemic. Even we have problem identifying patient zero for Covid-19. And a century ago, we blame Spain for the Spanish flu.

If pigs were blamed for some ancient disease outbreak, they were most likely to be innocent.