Google's John Mueller was asked on Twitter if using a dual stack IPv4/6 setup give you some sort of Google Search or SEO ranking boost with Google. John said no, it does not. John responded saying "No. There's no SEO effect for that. Make your site work well for users."
Here are those tweets:
No. There's no SEO effect for that. Make your site work well for users.
— 🍌 John 🍌 (@JohnMu) September 21, 2020
What is dual stack IPv4/6? With the dual stack solution, every networking device, server, switch, router and firewall in an ISP's network will be configured with both IPv4 and IPv6 connectivity capabilities. Most importantly, dual stack technology allows ISPs to process IPv4 and IPv6 data traffic simultaneously. So you do not need to worry if IPv6 is supported in this case, both would work.
Here is a simple chart that explains it from WhatIsMyIPAddress.com:
So no, while it is a cool set up, it does not help you get some sort of ranking boost in Google Search.
Forum discussion at Twitter.