> That post was written 20 years ago. I would hope that the migration would be more than "much further along", I'd have hoped it had been completed, like a deca

> That post was written 20 years ago. I would hope that the migration would be more than "much further along", I'd have hoped it had been completed, like a decade ago. https://www.google.com/intl/en/ipv6/statistics.html https://www.google.com/intl/en/ipv6/statistics.html Yes, the IPv6 migration has taken much longer than anyone expected. But this argument would have made more sense in 2015 when we were looking at 5% IPv6 deployment and very erratic growth. But it's not, we've been looking at 10% of the market gaining IPv6 support for the last 3 years and are now at 45%. Now granted, this is likely to be largely "new" devices, e.g. in mobile networks and in countries like India where these were hidden behind CGNAT before. But these are exactly the type of devices that an IPv4 extension header couldn't have reached either.