Asus routers still ship with IPv6 disabled by default, to this day. It makes perfect business sense, as everything still works just as well with v4 but single stack is less complexity so less support costs, etc. I’ve been running my home LAN dual stack for close to a decade, so I have native v6, but then on the other hand I ignore it for my networking stuff, ie I only set an A record in my dynamic DNS and never bothered figuring out how to make phoning home from other networks work over v6. It’s just not a priority and my lack of deep v6 knowledge would make it likely less secure.