That also makes sense considering the sheer amount of people. With that many devices and people, it just makes more sense than trying to NAT everything at the carrier level.
I wonder if China's ISPs are doing the same thing?
A year back the party decreed a plan to have all Internet users on IPv6 by 2025, with a quarter of them already by the end of this year [0]. There was a test rollout back at the beginning of the summer [1]. I guess we might see a huge rollout before the end of the year to meet the deadline. There's been a slight rebound already [2][3].
I speculate this is not true for China. ISPs in China have to deal with country-wide censorship system which has to be upgraded to support IPv6 traffic. This might be the reason why China has a low IPv6 traffic.
I wonder if China's ISPs are doing the same thing?