cluster-autoscaler can mange the machines easily, the point is kubernetes is an abstraction layer, using this level of abstraction is upto the user itself. Should i keep going down with container or using the node itself is the question, in production environment it makes all the sense to use something which has the potential to scale infinitely, but for hobby projects mental overhead doesn't justify using k8

You could say that Kubernetes "manages the machines" from the point of view of the application, by providing a suitable environment to execute in (including actually starting the application)