When I replace DHCP/DNS with Pihole I need to account for that. While this is not a complex setup once you understand IPv6 you still need to learn it.
I work in IT so I tried to get myself to IPv6 several times but never had any reason to do so (despite self-hosting a lot and generally being a nerd). I had to do that this time and my uninformed opinion is that it could have been done so that it is much simpler for advanced users (but not yet networking experts)