I would be amazed if 80% of XBL users are forwarding ports on their routers. I've never heard of this before.
Port forwarding has been a must for quality FPS match making since the beginning. What XBL games do you play?
So I don't think he's not "very informed." He's the normal player base. I don't even bother setting up NAT anymore and it works fine, even though I know I should go through the rigmarole of doing it.