Besides CNI networking potentially encompasses Services, Endpoints/Slices, Load Balancers, Ingresses and most recently the Gateway API. I'd say that's quite a bit complex.
Kubernetes allows you to make complex networking, which is especially useful for cluster setups involving multiple nodes. But if you're comparing kubernetes with docker, docker does not have load balancers, ingresses, so you can just skip it, if you feel that it's too much of complexity. They're not mandatory.
