Actually mDNS does exactly what they said just fine. You’re confusing it with the ability of a DHCP server to make updates in DNS on behalf of clients. There is more than one way to skin the cat. Both achieve the same affect, just differently.
> nor do they necessarily ever consider your local DNS server.
Hardcoded DNS servers are just as equally a thing with IPv4.
Rather, most routers add DHCP hostname requests to the local DNS routes. That doesn't require mDNS, nor would you want to replace it with mDNS as mDNS is more limited & flakier.
Ping foo on my machine results in foo.local being successfully pinged. Your mileage may vary.
> would potentially use mDNS if you have a ping that does such a thing
It's not a feature of ping, it's a feature of the name resolution setup on your machine (nsswitch and/or resolved on Linux).
> Rather, most routers add DHCP hostname requests to the local DNS routes
What do you mean?
Of course, but they aren't the baseline expectation like it is with ipv6 since ipv6 baseline assumption is SLAAC. And SLAAC is terrible. If you control all the devices on the network, like a cloud install, you can just pretend SLAAC doesn't exist and live in a much better world.
If it's a home network then you're stuck expecting at least some usage of SLAAC. And you're better off just not supporting ipv6 at all at that point
Why not? Are you saying your computer doesn't need to know the IP address of any dns server in order to be useful?
What do you mean when you say that SLAAC is terrible? Especially when you control all the devices on the network, you are in full control of what SLAAC manages for you. Also, SLAAC is the only way to use the IPv6 Privacy Extensions.
Things like RA and NDP would clue hosts into the local DNS server as well. You don't need DHCPv6 to advertise a local DNS server.