They’re not smart enough.
I don’t think we need to look any farther than:
(1) pigs are nasty;
(2) the “modern” method of farming pigs is very close-quarters;
(3) the Chinese take it a step farther and feed chicken pig crap and vice-versa and raise chickens with pigs -— literally with the wire chicken coops on top of pigs -— all in tight quarters with humans.
You stuff enough critters together long enough, nasty bugs crawl out of all sorts.
We have plenty of land in this world. If you have to eat swine, go raise pigs out in the open plains.
Your three points are correct and I agree. I disagree that they are not that smart. I’ve dealt with Islamofascist vermin; some are very smart and highly educated in the hard sciences. Unfortunately for us, they are also religious radicals highly motivated to apply their intellect and creativity to cause us harm.
Shalom and Regards.