Perhaps, but I'm not at all convinced. The hard problems of running distributed peer-to-peer services are not end-to-end connectivity. While that is a problem, it's a relatively small hurdle; you can connect the vast majority of clients with some not huge effort.
The much bigger problems are related to moderation, copyright enforcement, spam prevention, security. All of those are extremely hard if you don't have a centralized authority server.
Could Zoom have better quality more cheaply if it could easily do P2P connections for small meetings? Very likely. Could you make a fully distributed Zoom where anyone can call anyone else without a centralized authority server handling all calls? No, not without significant legal hurdles and effort on preventing malicious actors from spamming the network, from distributing illegal content, etc.
Also, back to middleboxes: not having NAT would not get rid of middleboxes. Even on IPv6, there will always be a stateful firewall blocking all outside connections to the internal network in any sane deployment, at least for home networks. And that firewall will probably be about as buggy as cheap NAT boxes are. And for corporate networks, you have all sorts of other middlemen critical to the security of the network, I clouding IDS and IPS systems, TLS listeners to protect from data e filtration etc. Those will interfere with your traffic far more than relatively regular NAT boxes would.
The much bigger problems are related to moderation, copyright enforcement, spam prevention, security. All of those are extremely hard if you don't have a centralized authority server.
Could Zoom have better quality more cheaply if it could easily do P2P connections for small meetings? Very likely. Could you make a fully distributed Zoom where anyone can call anyone else without a centralized authority server handling all calls? No, not without significant legal hurdles and effort on preventing malicious actors from spamming the network, from distributing illegal content, etc.
Also, back to middleboxes: not having NAT would not get rid of middleboxes. Even on IPv6, there will always be a stateful firewall blocking all outside connections to the internal network in any sane deployment, at least for home networks. And that firewall will probably be about as buggy as cheap NAT boxes are. And for corporate networks, you have all sorts of other middlemen critical to the security of the network, I clouding IDS and IPS systems, TLS listeners to protect from data e filtration etc. Those will interfere with your traffic far more than relatively regular NAT boxes would.