There is a ton of logging infrastructure etc. that would all have to be changed to do ipv6. And sadly, the benefit to individual users is little, as every ISP h

There is a ton of logging infrastructure etc. that would all have to be changed to do ipv6. And sadly, the benefit to individual users is little, as every ISP has ipv4 already. So other features get prioritized: https://meta.stackoverflow.com/a/348224 https://meta.stackoverflow.com/a/348224 Some major cloud companies also sit on giant piles of ipv4 addresses, like Amazon for example. They of course have negative incentives in ipv6 adoption, as they want their ipv4 investment, which lies in the billions, to pay off as much as possible. The ISPs on the other hand are heavily incentivized to support ipv6 because the less traffic there is via ipv4, the less load there is on their carrier grade NAT infrastructure. Furthermore, ipv6 allows for cleaner routing tables, at least that's the theory.