Peer to peer has been dead for more than a decade. Computers are all behind firewall/NAT, they can't connect to one another. Mobiles are behind whatever is the mobile network nowadays, it's outbound only, nothing can connect in.
Source? Some apps like bittorrent have increased in the past decade, have they not?
Peer to peer simply doesn't work since NAT. Skype used to be peer to peer but they backpedaled a while ago because this and more reasons that simply made p2p obsolete and broken.
It's too long to cover in one message. Would you be interested if I write a blog post? How peer to peer architecture became obsolete and why no software is using it.
In a scenario of 12 people video chatting around the world, I don't believe you could guarantee consistent high-speed connections between the involved parties.
Teredo tunneling was one of the coolest solutions to this problem, providing both NAT-busting and IPv6 support but unfortunately it never gained popularity.
Ya, I'd be interested in reading that! Could you address why it wouldn't work with NAT the same way bittorrent deals with it? I'm probably missing something, but I don't see why bittorrent can work so easily but video conferencing cannot. thanks
Edit: Does bittorrent require you to port forward? I didn't think it did, but I haven't seen it configured in years so maybe I am forgetting that step
Some machines can't be reached. Many others have UPnP capable routers and can reconfigure NAT for port forwarding on the fly.
Additionally more and more users have IPv6 at home. It's now high enough to be worth trying along with other techniques like STUN.