Network booting combined with good out of band management controls allows fully automated provisioning of nodes in a baremetal setup, so I don’t see how this is

Network booting combined with good out of band management controls allows fully automated provisioning of nodes in a baremetal setup, so I don’t see how this is a negative? The alternative is a live cd/usb or attaching a disk with something already preinstalled. If you’re on prem with VMware or openstack there’s better options which you can use, but that’s not exactly baremetal. in those environments CoreOS recommends using different provisioning options more suited for those providers.