That's a tautology: "Despite the limitations of IPv4, we're still supporting all the applications that can work within the limitations of IPv4".

Lots of potential P2P applications (that might solve a lot of problems with have with the current centralised model of the internet) either don't make it past the drawing board because of NAT, or have to be encumbered with complex, expensive-to-develop, best-effort NAT-punching behaviour that burdens everyone involved (and can stop an application from being truly P2P by having to run things like STUN servers).

>NAT seems to always get a bad rep because it inconveniences the very few that want to have an end to end experience

I think there would be many more that wanted this if it were trivially easy to do

>but there has to be some sacrifice to keep the Internet running for the billions of users.

What's the sacrifice in using IPv6?

Gamers get errors about "strict NAT." Traditionally the solution to this problem caused by NAT was to forward the ports. If their ISPs has chosen CGNAT port forwarding is impossible.

VoIP calls that have one way audio are a symptom of reachability issues caused by a firewall or address translation problems. VoIP services have adapted to IPv4 NAT by relying on proxying instead of STUN but CGNAT really degrades reliability.

Smaller newer ISPs that can't obtain one IPv4 address per household are incurring signicant CGNAT costs. https://news.ycombinator.com/item?id=35047624

Video chat uses the kludges of TURN when peer to peer connectivity does not work. This increases costs for the video chat service who in turn require a paid subscription as they will not relay traffic for free.

BitTorrent and file transfer services need direct IP connectivity. If p2p file transfers worked on any network we would not need to mind Gmail's 25MB attachment limit, or pay for intermediary cloud storage.

A CGNAT is a stateful component which makes it expensive to operate. Failover to a backup is hard, as is scalability with this kind of components. And then there are legal requirements. You have to know what user had which IP address at a given time. I'd rather invest in dual stack instead.