Given that IPv4 Evolved a lot over the last 20 years to manage the complexity of address assignment and shortages, everyone should be aware that IPV6 has changed too.
The chapter on IPv6 just barely hint and the development of IPv6 in real world cases.
Don't take an almost 20 year old book for gospel for IPv4 or IPv6.
Policy and implementation practice has changed enormously. Look at documentation from the last few years and from good sources. EG Apnic is the Regional Internet Registry for Asia. https://blog.apnic.net/2023/04/04/ipv6-architecture-and-subn...
Also a good source of info and opinions is the Packet Pusher set of podcasts. https://packetpushers.net/
I find that they tend to have a very real world explanation of topics covered and they avoid the "I've doing networking for 20 years. Don't tell I have to change" attitude.