The proposals that seemed backwards compatible were just aggressive CGNAT consolidating even more power in the hands of IPv4 address owners. That doesn't seem like a sustainable fix in the long run.
True, but it would limit that break to a single thing. That's much easier to deal with than the whole basket of things that IPv6 brings with it.
In general, despite the complex vocabulary about most of it, in many ways IPv6 is simpler than IPv4. Its header has fewer fields. Its QoL/QoS fields aren't accidental hacks on top of old debugging fields but intentionally designed fields for that very purpose. SLAAC is a simpler protocol than DHCPv4, though the algorithm sounds more complex at first. (DHCPv6 is basically as complex, but fewer devices and fewer subnets should need DHCPv6 in the first place.) Much of the "basket of things" that IPv6 brings with it are designed to remove complexity that has concreted around IPv4.
They ripped the bandaid completely off with the backwards compatibility break that they made with IPv6, and apparently a lot of people loved the cute stickers they had applied on top of the bandaid. But at this point it is probably better for the skin below to heal without the bandaid than to continue to sticker and bandaid over that and let all that unnecessary glue fester in place. (To push such a metaphor almost to its breaking place.)
It's not really about whether or not IPv6 is simpler than IPv4, though. It's about how painful moving from IPv4 to IPv6 is. And it's very painful. If the only thing that changed between the two was that the IP address space is bigger, it would reduce the pain of changing.
I'm certainly not going to claim that my experience is representative of anyone except for me, but the reason that I'm not going to shift to IPv6 until I literally have no other choice is because doing so is an enormous undertaking. Since IPv6 doesn't bring me any benefit that I care about, there is no reason to do so unless I simply can't get on the internet without it anymore.
Please note: I am not bashing IPv6 here, and I'm not saying that a change isn't needed. I'm just expressing some of the reasons I've seen why people resist changing to it, and that I think adopting it would have happened within a reasonable timeframe if it weren't as ambitious.
There's zero proof that an "extended IPv4" would have been adopted on a "more reasonable" timeframe, no matter how you define "reasonable" (faster, I guess is what you are arguing for?).
Exactly where and how do you expect "just add more address bits to IPv4" is an easier transition than IPv6?
The IPv4 header is a fixed size. You can't add more address bits without breaking existing routers. Period. End of technical story. You could embed the additional address bits in the next layer up (TCP/UDP) but you greatly increase the complexity of routing equipment by making it have to understand those layers, to what benefit? In the dual-stack real world we do that all the time with VPNs and STUN tunnels and other gateways and tunnels. We have those exact same tools, already, and those haven't made the transition any more "reasonable", have they?
But it's worse that while routers don't understand the extra bits, the parts of the addresses that get used (the prefixes small enough to fit in IPv4 headers) have to become massive NAT gateways and become massive gatekeepers of huge parts of the IP address space. We know from deep experience that IPv4 address allocation wasn't "equitable" (ARIN got way more space than RIPE and both got more space than AFRINIC and so on; companies like Microsoft and GE got /8 allocations just for asking in the right years).
Does it make that much sense to establish existing IPv4 holders as the forever "landlords" of the internet? That seems to me to only add more incentives to make the transition more unreasonable than IPv6: why support router initiatives that understand the additional address space when the IPv4 address holders can get "extra rent" if they don't, presumably charging all their "downstream" traffic for their gateway usage? We're in a time where IPv4 addresses have noticeable rental costs, I can't imagine what that would be like in a world where large parts of address space have to be on VPNs controlled by IPv4 owners. That doesn't sound to me like a good present or future for the IP protocol, no matter what.
None of these things are IPv6's fault.
Hell, give me remote access to your network and I'll set it up for you -- at least enough to get you started on it if not 100% on every single thing. I don't expect you'll take me up on that offer, but it'd be easier to just do it than tell you about it, since you can't tell people anything: http://habitatchronicles.com/2004/04/you-cant-tell-people-an...
The only pain I've ever seen is in corporate networks where all the tooling around the network management are IPv4 only but those would break even if you add a single bit to an IPv4 address.
