> At the tiniest scales, Kubernetes stops making sense because it's too complex to manage.

Managing k8s at the smallest scales is actually easier IMO. If you're using a managed k8s (you should be) then there's not much to actually manage. I've been using single-node clusters to great benefit for my business for years. Let's me focus all my time on billable hours and product updates. Huge force multiplier for me as a solopreneur.