Re:spoilage Even if there's nothing specific to pork, the size of the animal may present that challenge. it's harder to time the slaughter and butchery if a larger animal. If you've been raising an animal for a year, you're going to want to eat all the meat. So you need to save it for celebrations, or barter, or eat meat that's been sitting around. Pigs are pretty big, assuming all domesticated animals have increased in size roughly equally.
But the kosher prohibition isn't "don't eat meat slaughtered a week ago", which would be easy, it's about cloven hooves.
The other hypothesis I've seen put out there is that viruses tend to have an easy time jumping from (living) pigs to humans. We think of the flu as relatively minor now but without clean water it would be a big deal.