No I’m arguing that NAT isn't a security feature, and wasn’t meant to be a security feature. The fact people sold it as a security feature, and the fact that it might incidentally behave like a poor firewall, doesn’t change the fact that NAT isn’t and never was meant to be a security feature, good or bad.
I feel like I've provided black-letter proof that it was meant to be a security feature; the commercial product of its inventor was a firewall that advertised NAT as a security feature. I don't really understand how you can argue around that.
Nobody's reading this thread anymore, so why don't we leave our arguments where they stand.