I'm sorry, what precisely has changed in the past 35 years that makes reaching vital organs and the CNS no longer relevant to ending a fight that may involved a determined or altered mental attacker not susceptible to a psychological stop?
Or rather, what has changed in the last 3 years?
since you used the "tired old" argument to justify 9mm over .380...
Your priorities seem to be
1. Do not overpenetrate
2. Stop the threat
In that order, precisely the reverse of many others and that's why it's so fascinating to explore. Which is fine, again I'm not here to change your mind. However, if that logic was applied consistently, it would mean something like underpenetrating .380 JHP loads, or even .22LR would be superior to 9mm, with underpenetration being a feature even, and surely you're not advocating for that? You didn't add a caveat in the above post suggesting that in the niche case of home defense .380 would be superior, so I have to believe the difference between then and now is simply how impressed you are at the devastating damage birdshot causes at very close range, while ignoring that even within the span of an interior home you can easily exceed the distances at which birdshot inflicts those very wounds.
Your second point is understood by all, but you seem to keep dismissing instances that
do happen and
have happened as unlikely to the prototypical encounter you have in mind, and therefore irrelevant. I'm not sure it's wise to bank the farm on reality itself being flexible so as to fit around your conclusions instead of the other way around. "It's not the odds, it's the stakes", is foundational to anyone who carries a gun, at least I thought so, and it isn't best practices to assume best case scenario in a self defense situation in which the deck is already stacked against you.