I think it’s going to be a long time before IPv6 becomes the norm. My opinion is at least a decade or more. Although the Internet is well on its way to becoming fully IPv6, adoption is still very slow at less than 35% worldwide, keeping in mind that this level was at 5% at the beginning of 2015, and the increase seems to be linear so far. Fewer than 5 countries have achieved more than 50% of adoption.
But these are statistics that have to do with the use of IPv6 on the Internet. I believe that internal enterprise networks are going to be even slower in adoption. This is because all of the measures taken to increase the longevity of IPv4 have been too successful, making it easy to keep your IPv4 networks in an ever-increasingly IPv6 world.
I live in a country that is among the top ten in the adoption of IPv6 on the Internet, but I have yet to see any large scale private or government network adopt IPv6, except for an experimental network maintained by several universities. It’s just too easy to keep using IPv4, at least for the time being. The investment time and effort to upgrade is not worth the benefit that IPv6 provides over IPv4 on steroids.
Just my thoughts.
That’s one of the things that makes networking so interesting! You rarely get bored!
I hope this has been helpful!