It's very flawed, but the flaws are very well understood and people actually seem to like operating all these workarounds.
Not saying that's good, just what I'm seeing in the field.
The greybeards philosophy is how it initially was. There aren't multiple networks, there is supposed to be ONE network, THE internet with ONE global address space.
The philosophy of those who grew up with NAT, who think that sounds insane. The internet is just the glue network between heaps and heaps of separate networks, each with their own, enclosed address space. Why would you want all networks to be one network, why should your printer have a globally-unique globally-routable address?
The two different philosophies don't tend to get along.
It's perfectly fine to run a separate network. You can do that and still access Internet hosts easily by having one machine that's on both networks and running a proxy on it.
But nobody wants to do that. Almost everybody actually wants to be able to route to the Internet and back, so they set a router up to join the networks, and then (on v4) they have to NAT because nobody will give them enough v4 space for their network.
Unfortunately there's a severe lack of understanding of basic networking concepts and of what routing and NAT are doing, even in people who work in the field.
You actually do want your LAN devices to be routable from the outside, because you want them to be able to talk to Internet hosts and you want those hosts to be able to reply. That's the real reason you have the router.
What you probably don't want is for people outside your network to be able to initiate new connections to inside of it, and that's something you get with a firewall, running either on your devices or on the router.
NAT only comes in to any of this if your ISP can't issue you enough address space to use on your LAN, without which your network won't be routable even with a router in place. NAT is the big hack to try and get routing to work without sufficient ISP-assigned address space. It's not needed for anonymity or for getting a single point of control.
I do not. I certainly don't want the internet to know how many devices I have and what they are. Traffic to and from the LAN should be anonymous. As far as the internet is concerned, my LAN is a black box.
> It's not needed for anonymity or for getting a single point of control.
NAT used that way usually, because other solutions are lacking or too expensive, and because the people who invented IPv6 didn't bother trying to solve real problems.
NAT applies on top of routing, so you can't use it without routing. If you're using NAT, then you've made your devices routable. Whatever you say about not wanting to do that, you did do that, so it must have been preferable to you in some manner or another.
I know this would contradict your claim that you only have a router to make your network unroutable, but that claim never made any sense in the first place. It's the job of a router to make a network routable.
> NAT used that way usually, because other solutions are lacking or too expensive, and because the people who invented IPv6 didn't bother trying to solve real problems.
Nobody is using it to get a single point of control. In order to NAT you need to set a router up, which means you already have a single point of control. There's no need to also do NAT and it won't help either, so it's not being used for this.
It's not usually being used for anonymity either, because most people using it only have a single IP address in the first place and that's the one all their NATed connections appear to come from. They get no anonymity from NAT.
The people who invented v6 did bother trying to solve real problems. But getting a single point of control was never a real problem and didn't need solving; the real problem was the lack of address space, which they did solve.