I've tried to run an IPv6 only box on Hetzner 2-3 years ago. Didn't have a problem with the platform, but with RedHat because subscription-manager didn't work over a IPv6-only stack.
When I accidentally had IPv6 only for a new Windows box it was very apparent what was a priority (worked regardless) and what wasn't important (only began working once I had IPv4 and everything fixed too).
Baked in advertising? Works with any network. The option to turn off the baked in advertising? That needs IPv4.
Baked in advertising? Works with any network. The option to turn off the baked in advertising? That needs IPv4.