v6 actually is pretty close to a wider v4. There are very few new things in it, the socket API is the same for both, and parts like addressing and routing work

v6 actually is pretty close to a wider v4. There are very few new things in it, the socket API is the same for both, and parts like addressing and routing work exactly the same. It could've been very different, but it's not. Running v6 is similar in complexity to v4, but a lot simpler than v4+NAT. Since NAT is more or less a necessity in v4 these days, v6 ends up being simpler in practice.