For ISPs (and mobile carriers) that are actively involved in their infrastructure, CG-NAT is more expensive to run than native ipv6 (aquiring IPv4 public addresses; tracking connection states; if all customers are on private IPv4, maintaining multiple distinct private networks with the same address space is a hassle too), so those ISPs are pushing to make services available over IPv6 (I've heard from T-Mobile USA and Jio India), but that doesn't mean they won't also run CG-NAT for customers on older devices and for services that aren't IPv6 -- it just reduces the deployment. For smaller ISPs, or where everything is contracted out, the cost savings aren't as apparent.
> it's no wonder the transition to IPv6 has stopped
Where are you getting that from? Looking at public IPv6 statistics from big companies shows that it's going up.
Google's shows a 4.5% increase in IPv6 of total traffic during the past year[0]. Facebook's shows a 6% increase and at 55% for the US [1]. Meanwhile Mexico went from 5% IPv6 to 25% this year [2].
These statistics are meaningless propaganda. What you should be interested in is the velocity of IPv6 adoption growth among ISPs and countries where adoption stopped all together, to know what to expect from actual adoption in coming years. (it's basically a failure btw)
> What you should be interested in is the velocity of IPv6 adoption growth among ISPs and countries where adoption stopped all together, to know what to expect from actual adoption in coming years. (it's basically a failure btw)
I don't understand. Are you telling me to look at how IPv6 adoption is among countries, where IPv6 usage growth has stopped? Are there any such countries?
Furthermore, I'm not sure what you mean by "actual adoption". Every statistic I look at, as referenced in my previous comment, I see IPv6 usage continuing to grow. And you're calling that "propaganda"?