Arguably, the design of kubernetes is for clusters to be based on physical clusters - to the point of a cluster per aisle (or multiple aisles), and resources of those clusters then being used to deploy applications even across clusters. Or in the small, like Chick-Fil-A, with kubernetes running locally at every restaurant.
Not just past 10k node limit - it's also because the k8s design has unsaid assumption about being used to arrange physical sets of machines, similar to how Borg paper would talk about cluster being equivalent to an aisle in datacenter.
Are you just referring to how you assign labels and taints to nodes, which in a physical datacenter could include labels like which aisle the baremetal server is in?
Of course that's feasible, to tell the Kubernetes scheduler that you only want to schedule the workload on a very specific server, but that's not really best-practice...
