On the other hand, if you want to play games on your network you absolutely must have UPNP. Unless the game has a dedicated server infrastructure. But even then you risk higher latency on VOIP if it even works at all.
Also STUN for VOIP does not increase latency. It tells you your external IP and port.
Edit: Port symmetric —> port restricted
You can port forward of course, but you have to know which ports and obviously it only goes to one static IP
And, don't quote me on this, but most PC games are not Peer-To-Peer. They often come with their own server software.
Heaven forbid you have a PC game and a Xbox game that have conflicting ports.
And, I just have to say: you open arbitrary ports to your game console from the internet and talk about security.