That's because you're using stateful DHCP which the kernel doesn't do.
My comment was about a stock setup which comes with stateless DHCP, in which case all Linux distros do get a configured IPv6 address regardless of what their userspace does, so long (and that was the problem with nplan) as the interface hasn't been directly configured not to do auto config.
That's because you're using stateful DHCP which the kernel doesn't do.
My comment was about a stock setup which comes with stateless DHCP, in which case all Linux distros do get a configured IPv6 address regardless of what their userspace does, so long (and that was the problem with nplan) as the interface hasn't been directly configured not to do auto config.