The short answer is no, but the longer answer is "it depends". If you setup an environment manually, such as by following something like Kubernetes the Hard Way, you will install and configure the Kubelet manually on each Node. It will run as a Daemon. Then, it will register the Node with the API server, and then the Kubelet will be utilized to schedule pods/containers to run on the Node. In this way, Kubelet cannot be a Kubernetes DaemonSet because it is needed to bootstrap the Node to begin with (you can't use Kubelet to schedule itself to the Node so that it can then schedule Pods).

However, cloud providers may do all kinds of interesting things to provision clusters in different ways, so I would not go as far as to say that kubelets are never DaemonSets.