They squashed kubelet, not K8s. By that, they probably mean that they got rid of the kubelet and delegated its functionality to systemd (which is already there

They squashed kubelet, not K8s. By that, they probably mean that they got rid of the kubelet and delegated its functionality to systemd (which is already there besides the kubelet if the node uses systemd based distro). Note that quadlet is also capable of creating services based on K8s manifest.