The thing is, it's not v6 or v4, it's v6, v4 with a price premium, or v4 with CGNAT.

CGNAT sucks. Stuff blocks you because you get lumped in with other users. You can't take inbound connections. Average users don't know that, but they get annoyed with side effects. Not being able to play multiplayer stuff or it being slow/high latency because of no inbound connection. Having to do extra CAPTCHAs, being straight out blocked, etc...

Price and annoyance are absolutely things people want to avoid.

I guarantee you at some point, some ISP is going to realise they can market themselves as the gamer ISP and sell IPv6 as the option for pro gamers to ensure the lowest latency in their games. CGNAT will be the congested roads, IPv6 the open motorway. (To be clear, it obviously isn't that simple, but I'd put money on that's how they'll sell it.)

I agree that CGNAT sucks -- for the user. But users don't exactly have a ton of power here. And CGNAT is mostly fine for anyone but power users; I've never experienced being blocked or excessive CAPTCHAs when on a CGNATed cell network.

> I don't see any "dash" to support v6 in our future, when the option to just keep working around issues with v4 is so much easier and cheaper in the moment.

30-40% global adoption in ~10 years may or may not be a "dash", but it's also not nothing.

"easier and cheaper" is very much not the case at larger scale. legacy ip space is only growing more expensive, & cgnat platforms are not cheap. even if a carrier HAS TO deploy cgnat, deploying ipv6 first means you don't need to buy cgnat capacity for any v6-native traffic (which is a non trivial volume)

> Really, what does anyone have to gain by switching to v6?

the above, & also a future-proofed, infinitely scalable network. any org's that do alot of m&a don't have to play as many stupid rfc1918 integration games.

if you don't deal w/ scale, yea, hard to see the benefits. fair.

> 30-40% global adoption in ~10 years may or may not be a "dash", but it's also not nothing.

Still nowhere close to being remotely unusable after soon 30 years is very very close to nothing.

Regarding benefits: Amazon, Azure and all the other major VPS companies has a lot to gain from IP addresses being expensive, since it makes it almost impossible for new players to enter the market. ISPs may pay for CGNAT in terms of infrastructure and complexity, but they save in support and abuse mitigation cost by making it impossible for normal people to host their own stuff, they save in support cost by not dealing with customers' broken products which get confused by IPv6, and they gain financially from charging a ton for "pro"/"enterprise" non-CGNAT connections.

And for any kind of web service, supporting IPv6 is obviously just a net negative, since you have to deal with both v4 and v6 rather than just v4.

So I suppose I'm saying, sure, there are minor things to gain from v6, but it's not clear that they outweigh the (opportunity) cost of v6 for anyone, and for large sectors it's simply a cost with no upside.

I don't see a rush to support v6... ever. We'll keep growing steadily but slowly for a while, then adoption will taper off.

But hey, I may be wrong! I'd certainly be happy if you were right. The minuscule amount of progress across almost 30 years doesn't instill confidence though.

What I think (or at least hope) that this post is missing, is the ever-growing opportunity cost of having a population of people that are flat out unable to access your service. Google's IPv6 page currently has almost all of Africa at near-0% v6 adoption, but this map https://data.worldbank.org/indicator/IT.NET.USER.ZS?view=map shows a lot of African countries that still have low internet access. With such a long way to go towards full access, and in a lot of countries, exponentially rising populations, could a lot of African ISPs give up on the cost and/or CGNAT complexity of trying to magic up so many new IPv4 connections, and go all in on v6? That's only my layman speculation though.