I'm not looking forward to asking my parents to visit http://[fe80::abcd:whatever] to access their router interface when something goes wrong. Hopefully they'll be able to use basic numeric IPs for the rest of their lives.
Depending on OS, you might need to actually put the interface name in there? As you can have fe80::1 on multiple interfaces...it being link-local. Maybe browsers are holding it back?
My ISP provided router responds to homerouter.cpe with both IPv6 and IPv4 address of its router webui.