Well, we'll have to see what all the "in-between" bits do. There's a lot in it, that will require implementation by countless layers of routers, switches, caches, firewalls, etc.
Look at Bluetooth, for an example, or TIFF.
I printed out the Bluetooth spec once, just for Ss and Gs. It was over 2,000 pages (double-sided).
I once tried writing a fully-compliant TIFF reader. Didn't go so well.
Those all support IPv6 too. They’re the same computers, and they’ve all supported IPv6 for decades now. The IPv6 spec is a lot shorter than the spec for Bluetooth or TIFF.