[Dagger2]

And in this common configuration, NAT does nothing to prevent inbound connections.

[icedchai]

Do you admit using RFC-1918 + NAT provides some security even with no firewall for the majority of residential users?

[Dagger2]

Neither of them prevent inbound connections, on their own or together.

I don't really think that "inbound connections work fine and you're basically just praying that the people that can do them simply won't" counts as being secure, but I'll admit that using RFC1918 does limit the set of people that can do them. If you made that your argument, you'd have more of a point than an argument based around NAT.